My family is falling apart.

I just turned 21 yrs old, I have 3 older brothers, parents are still together, & I’m still living at home, I have a boyfriend of 4 yrs. My oldest brother had a near fatal overdose 2 yrs ago (he’s doing better than ever now), but ever since that happened, it seems like my family has slowly fallen apart. My other brother has had a kid since then, and he’s been a complete mess since she was born. He randomly lashes out especially on my parents for no reason, he’s VERY disrespectful when he gets in these moods. I think he is bipolar, but refuses to get help. My mom said she found little bags with residue in them in her car recently, I think he may be doing drugs now. I saw on his record he has “prohibited acts-possession”, so who knows. My parents are getting eviction papers today & he’s going to blow up, but this has been going on for far too long. My parents fight a lot, my mom is a mess. My mom told my dad that it’s his fault that their kids are addicts because my dad smokes weed, which is ridiculous because that’s the only drug he’s EVER done. My boyfriend wants to move out of his house soon & asked if I would like to come & I said yes, but I still need to go back to college, but idk what I want to do in life. I should probably find a new job before moving out (I only make $11 an hr) and I’m also very anxious to be on my own. I don’t know how to do a lot of things in the real world, I’m nervous to get a new job (I have bad social anxiety), I’m nervous to ever go back to school. I feel like my home is just very toxic for my mental state. I feel very lost, everything is sucking rn. I’m on medication for depression & anxiety, maybe if I start therapy, I’ll be able to figure out my life. I’m just so lost and depressed honestly.