I feel bad about this

Over the years, my relationship with my family has been strained off and on. It was strained during my teens, and it got better in my 20s. Now that I'm in my 30s, I can tell that I'm cycling back into a strained relationship with them again. I feel guilty about this because it's happening one year after my mom died. My main problem is that I didn't go through individuation at the developmentally appropriate time due to anxiety and being risk averse (which was praised as maturity), and my family knowing almost nothing about mental health. What doesn't help is that I spent the last 9 years of my life believing that I'm autistic when I'm probably not. My older sister convinced me of that. Now I feel like I can't trust her, and anytime she offers me help or reassurance it feels intrusive. Sometimes, I get irritated over small disagreements or misunderstandings; I have the insight to know my irritation is unwarranted, yet I do it anyway out of instinct. I really need to pull myself away from my family's orbit and live my own life. Until I do that, I'll never be free.