Should I keep contact with my mom or cut her off?

I (18 m) am getting ready to go to college. My parents got divorced when I was 15, and I primarily stayed with my dad to try and help him. My dad died last February from liver cancer, and afterwards, my mom moved into his old house because he asked her to look after me, who was 17 at the time. In March I started working at a restaurant after school, and in late March/early April, my mom moved out to live with her boyfriend an hour away. She still pays the house note, I pay the rest of the bills. I talk to her sometimes, but it has also affected my financial aid for college because she got married this past May. I really don’t know what to do, and I feel like I need some help from an outside perspective.