Wow, everyone sure has more pessimistic views on the ending that I did when I first read it, lol...
I definitely don't think it's a Yuri ending, but i think it's a happy ending nonetheless. It's clear that MC's friend is a damn good one, who took off from her first date (seems her new boyfriend is a good guy too), bought her stuff and went to her friend's aid cause she thought she was sick. I think the friend is straight but you can tell she really cares for her friend and will be there through thick and thin for her. I think that's a positive ending.