Back story; I have known this girl for pretty much my whole life. We are both 24 and only about a week apart in age, our dads have been best friends forever, and I truly care for her and her family, but every time I hang out with her I just feel like I'm not being respected as a friend.

We both have babies. My daughter is 8 months old and her youngest is 7 weeks. I have been wanting to go to the gym to work on my body and to help me feel better and I offered her to come with me to have a workout buddy. Her parents said they would watch my one kid and her 3 kids so we could go. She asked if we could go try to confront the possible father of her youngest because it has been weighing on her heavy and I told her yes but I still wanted to go to the gym. She said okay. So long story short, she confronted him, he wanted to see the baby so basically ran around all night for her and for her problems. I mentioned the gym and she just said I'm sorry, but kept asking me to like be there with her for moral support. We left for the gym at like 7:30 pm and I didn't get home from being her "moral support" until 2 am. I have a life. A daughter. College work. And i'm starting work next week. I just dont see myself being her friend anymore as she knew I had all these things going on and she kept guilt tripping me and dragging things out.. I know that some people will say to stand up for myself or it is my fault but I really just wanted to be a good friend to her and she always begs me to keep staying longer and longer and basically wants me to be there for her whenever I can, like drop everything i have going on and I try to explain i cant and it seems like she doesn't really care about my feelings..

How do I cut her off ? I need some ideas on how to do it kindly and not so much as ghost her or tell her off because that may cause conflict with my father and hers.

*update to add*

No this isn't the first time she has gave me the run around or chosen herself and what she wanted over what I wanted. I was there for her through confronting him. She didn't need me after that for moral support she used that excuse to make me feel bad. She tried making me stay there all night with her, even after he went to bed she kept me there trying to talk and so she wasn't "alone" with him. I kept telling her I needed to leave and she again made me feel bad saying she was going to cry because of the situation but also decided she wanted to stay the night there with him and tried conning me into staying the night.

It isnt just about the gym. It is about me having feelings too and her always taking precedent to me and my feelings. Im fine being there for a friend but as I mentioned she does this a lot.