Dated for a year, she ended the relationship 8 weeks ago. Barely spoke for the first 4 weeks. She would text me or call like 3 or 4 times a week to "see how I was doing." About 4 weeks ago we hung out. Ended up having sex. That continued for about 2 weeks, give or take. The last two weeks though, everything has basically transformed into a relationship, but without the title of one. I go to her house after work, she makes me dinner, we hang out all night, have sex, I sleep over. We go out to eat, we go to movies, go to the beach, etc. etc. She says that she "doesn't want to be in a relationship" though. She said she has really strong feelings for me still, but she's going into her senior year of college and she doesn't want to be "tied down." Even though I am happy now, I think this is pretty unfair. Should I just keep going with the flow a little longer, or should I give her an ultimatum that we are either in a relationship or I'm gone?