AITAH for family overstaying their welcome?

My father had an affair before I was born (over 30 years ago). He got back together with my mom and had two children before going back to her. Now they are buying a beautiful house together. My parents are divorced. He lives currently with my brother who is younger than me for savings (moving very soon),but my brother is an adult (upper 20’s). My mom moved into my 2 bedroom apartment with me before I move out (also upper 20’s). My mom has paid half of their previous rent, and now allows my brother to stay with us and take over the kitchen all of the time when my dad is gone. I wouldn’t have a problem with this if we were in my family home or something similar, but I am approaching 30 and wanting to live my own life again. There is no space for this. We fight constantly and it’s destroying my mental health. AITA for having an issue with this? I left home after I went to college and now everyone is in my apartment I’ve been in for over 5 years,like it’s our family home, in a different state.