My mom never asks about me.

You don't mentnion how old your Mom is but what you describe are the early symptoms of dementia: talking a lot, lack of empathy, anger over minor, irrational things, easily confused.

Does your Mom have a PoA? If not, she really needs to make you or someone her PoA so that she can have a legal representative and advocate (think managing her financial assets, making medical decisions for her, finding higher levels of care for her, etc).

She should first see an elder law attorney to get her legal docs and ducks in a row, then you need to take her for the free annual physical covered by her Medicare and discreetly ask her physician to to a cognitive and memory exam.

Legal docs first, then the cognitive exam, in that order.

You say, "My mom has dealt with a lot of trauma in her life..." I say, "And there's going to be a lot more." There's nothing you can do to stop her from having more trauma. We all have it. Some people figure out how to get out from under it. They're called "resilient." Others figure out how to shovel their trauma onto others. They're called "dependent whiny moms."

Instead of trying to become closer to mom by being the good daughter who MUST make it up to mom that her other daughter died, insert distance between you. Don't jump when she says "frog." Don't dance when she says "tango." Figure out your own music and make sure it doesn't take you any closer to mom's orbit. Then maybe mom will finally figure out, "Oh! It's me! It's my problem! I have to fix it by (1) taking a sleeping pill (2) getting knee replacements or (3) flying off to Kansas on a tornado and seeking out the Wizard of Oz so I can find out what I need to be happy."

You're enabling mom. She needs to become an adult. She needs to fix her mobility issues with the help of the medical community instead of you. Guess what - I have a daughter, and I lost another adult child a few years ago, and sometimes I don't feel well or cheerful, especially since I'm sole caregiver for my husband who gets worse every day. And I've had more trauma in my life than you can imagine; in fact no one could imagine what I've been through both as a child and an adult. BUT I WOULD NEVER CALL MY DAUGHTER AND DUMP ON HER LIKE YOUR MOTHER DOES TO YOU! NEVER! I think too much of my darling daughter and love her too much to drag her down with me (after all, she lost her sibling), and I don't expect her to bolster me up, obsess about my health and how she has to travel here to fix everything, etc. Because it's not her job to do that. It's mine alone.

Good luck. You'll feel better when you stop involving yourself so much and let mom deal with her own life.

Have you talked to her about AL? She will be with people her own age, activities, she will also not have to cook or clean.

Isolation from people their own age is detrimental to elders.

Her actions of Me, Me, Me are a sign, dementia is in the house, this will not get better, accept that, time to consider some new options.

Guilt, there is no reason for that, you did not cause her issues, you can't control them or fix them for that matter.

Sending support your way.

My father was just like this. I can only tell you what was helpful for me. First, I lowered my expectations to near zero. My dad wasn’t interested in me, or anything going on in my life. There are probably many reasons for this, none of which I had any control over or ability to change. So, I accepted that. I realized that his world was becoming smaller and smaller, and he was becoming more and more self-focused. I viewed that as sad and pitiable. Most important, I got clear on my own boundaries. I was resolute in my belief that I was not responsible for his emotions or happiness. That was on him. I took on a lot less of his baggage. It was very heavy, and it was not mine to carry. And I didn’t want to. On her getting you to do things she could and should do for herself, I read on this forum, copied and pasted it on my phone to refer to— this is more about her proving over and over that she can get you to do things. It’s not about the task itself. So stop. Another line I leaned on heavily, I think from BarbBrooklyn who has helped me immeasurably: “I couldn’t possibly do that.” Complete sentence.

Guilt means that you are the CAUSE and you could FIX this if you chose to.
Neither is the case, so your guilt is not appropriate.
Rather change it out for the word "grief" which is appropriate here for both your mom and yourself. Grief can't be fixed. It must be moved through.

We tell people who we are by what we allow them to GET AWAY WITH.
If you continue to let your mother treat you this way, she will continue to do so.

As adults we understand that life isn't about "happy-all-the-time". There are hard times and hard times when they don't go our way. In other words, that's life.
Time to start protecting yourself. When the conversation goes South get off the phone at once. Just a "bye Mom. Love you. Will call when you are feeling better or in a better mood".
You owe this to yourself and your own family.

You are unlikely to help your Mom through her grief at the loss of a child. Of all people least able to help in depression, family members are the most useless. Suggest counseling and support for her grieving. Good cognitive therapist or grief support group.

You can't fix this. You aren't god. You're just a daughter trying to help.

I know this is not going to make it any better to hear this, but there's only so much you can do from 3 and a half hours away. I know, as that's how far away I lived from my dad who had dementia. A lot of elderly people (NOT all, I'm not saying that at all!) get that way...where they really don't think of you any more at all, but certainly my dad (with dementia), and now my mom (they've been divorced over 50 years, and live at opposite sides of the state) is becoming increasingly self centered. Some times it's hard, but I try not to take it too personally, as they are in a different place in their life than I, so there's no way I can know exactly what they are going through.

Anyway, please try not to beat yourself up about it too much as it WILL impact your health, and then your mom might end up losing both daughters before she goes. Where will she be then?

When I would go down to visit my dad (3 1/2 hours away), I had to NOT clean his kitchen each time, as the counters would be piled over a foot high with stuff that had no business being in a kitchen...it was just too exhausting emotionally for me to do it. Luckily, no food was ever left out on the counters or in the sink, as if it was in front of him, he would eat it. I focused more on making sure his refrigerator was cleaned out of all the food he would buy and would rot in there (example: 3 month old ground beef the first time I visited) since he would forget he bought it, and doing his laundry and taking him shopping. I also tried to help him get rid of things he no longer needed, which opened up his living area a great bit.

Try something like care.com and find and inteview someone who can come and help her as often as she needs it...on her nickel, even if you are writing the checks for her (out of her checking account).

I paid a friend of my dad's (I think the friend was maybe 15 years younger than my dad, and it ends up has COPD....) to help him (out of my dad's funds, of course). That worked for a few months, until he (the friend) couldn't take it any more. My dad (86) had dementia, and he had just declined to where he was calling his friend like 30 times a day, and needed full time care.

At that point, I told my dad he was out of options, that there was no one else to help him (he lived in a very remote place, where indeed there WAS no one available to help him), and he finally agreed to my putting him in an adult family home near me so I could visit several times a week while working my more than full time job.

I knew I could not care for him, as I've read on this forum how it's too much for one person, and certainly it would have been with him, as he was sundowning, not sleeping when he should have been, and his short term memory was shot. He would not make a list of things he needed at the store so they could be purchased once a week....he wanted things NOW when he wanted them. I would have had to quit my job, impacting my marriage and life, and most certainly, my health. Even so, I took on the care of his 15 year old dog that (a bit over 18 months later) I had to put to sleep as she was unfortunately at that stage where I knew she was in probably constant discomfort.

This might not be where you are at this point, but the point is that you can only do so much...YOUR life and YOUR health must come first, otherwise they (your loved one) will be gone at some point, and your health might be beyond recovery.