How do you help your parents?

I moved away when I was 16 because of an unstable home life. I didn’t finish school, I became pretty responsible and hard working immediately. My dad has never held down a job well and cheated on and mistreated my mom a lot. Very poor money management. They are in their 50s now, living in a camper and my dad is getting too old to do the handy man type work he does. Everything is his fault honestly but I still feel bad for my mom and dad, and my older brother who still lives with them doing his best to help but ultimately ruining his life cause he doesn’t know anything else but to live that life of constant struggle. I send them money but I am a single woman and I don’t always know how I’m going to do it. But I wanna help….My mom is so depressed and really feels like she wasted her life loving a man that made her life this way. It’s hard to see how miserable she is…she’s never been able to work or have her own car or friends cause we moved so much. She just raised me and my brothers..I told her she can come stay with me if she needs to. I just have a one bedroom apartment. It’s all so hard to watch. I don’t see how they can live this way forever, what are we even supposed to do for our aging parents? And still be able to take care of ourselves and save for our own futures?