For context, I'm male (22), but when I was around 12 or so my 'dad' had just decided out of the blue to drop me and my little brother and not talk to us anymore. He didn't even tell us he had gotten married even tho initially he had promised we could be in the wedding.

We made multiple attempts to try and contact him, but he never answered so we left it at that and tried to move on. Well when I was 18 he randomly called my mom and wasn't making any sense, was talking about us like we were still kids and like he was still married to our mom. We later found out that because of dr*gs he had completely fried his brain, lost his job, lost his wife, and had to move in with his mother because he lost his apartment too. He had tried to reconnect with us but at that point it had been 6 years, and I didn't want to connect with him anymore bc he had that chance.

Well I'm 22 now and a few months ago his mother called my mom and told her that he had passed away. She hadn't made any attempt to call us when he was sick, or when he had died, we found out after he had already been cremated. And apparently she had signed the papers, and left him in the hospital to die alone. A few weeks after he had passed my mom had had to go pick her up bc she'd had a stroke, and she hadn't cleaned her apartment in literal years. Roaches and maggots, dirty moldy dishes and mildewy laundry everywhere.

But my mom, the saint she is, helped her clean and move out into her local nursing home which was a 6hr round trip drive. My mom wants the best for me, and asked to give her my contact info bc she doesn't want me to have any regrets or bad blood with now how little time my grandmother has left. But honestly, she enabled my dad, never once helped him get help or get better, dropped us like we never meant anything to her, and left him to die alone, so I'm angry. AITA for not wanting to make amends with her? I feel bad bc she's got less than 6 months left, but I'm also still so angry at her.

UPDATE: So I took y'all's advice and did end up reaching back out to ask my questions. However I only ended up getting to question one which was why did they never visit, especially when they had plenty of opportunities as they drove through our town many times and could have stopped by whenever, and her answer was that paying child support was stressful and they didn't have the money to pay it but that my dad loved me and she regretted it. Obviously that didn't answer my question so I responded back saying that I can understand money troubles but that wasn't what I asked, then re-iterated my question. I haven't heard back and it's been almost two weeks.