This is gonna sound childish but...

How do I make friends? I'm 19 years old, about to turn 20. My last best friend and I got in a fight. She was angry and in retaliation she told my boss (and landlord) that I had threatened her. I didn't, but because I had a key to her room (I was an RA for my college) they didn't want to take any chances. I got fired and kicked off of campus. I've been living at home about 30-45 minutes from college. I lost all my friends when that happened because all of them were people I knew through her. I don't talk to anyone I went to high school with and all my college friends were people I knew through her. I have a guy who is my fwb, but I feel like I'm annoying him by constantly wanting to hang out. My grandmother has been sick so I've been going to class and then coming straight home to take care of her until my mom gets off work at 7pm. At which point I generally am crawling out of my skin from being with her all day So I go try to hang out with my fwb. So I haven't had a chance to get a job yet. I don't know how else to make friends...