Leaving home when your mom is a single mom...

I’m 21 and I’m leaving in a couple weeks to get an apartment with a roommate and I am so just distraught about leaving my mom at the house to live by herself. She’s been single since I was a kid and we’ve been each other’s best friends. All we’ve had was each other. I just feel really bad about leaving, and almost want to bail on the whole thing, just to make my mom happy.

She isn’t visibly upset but when I try to talk to her about it, she just keeps telling me I need to just stay at home and I don’t need to move out.

I feel so torn at what I want to do and what my mom wants me to do, and so upset at leaving my mom. Has anyone been through this before or have any advice at this situation?