Help with a girl. what should i do?

I met this girl a while ago. we had the same cl together, and i really liked her. the only problem was, she had a BF. ten, one day, i came into the cl, to see her crying. she told me her and her BF broke up. igave her a bunch of sympathy, and literally gave her a shoulder to cry on, and hugs. everything. then, a week later, her and i moved to theback of the cl together, alone. she got pretty flirty. she even came up with an inside joke about us being "like married". then the term ended. i only got to see her about once a day. she still refered to me as her husbund, even to her friends. i was oing to tell her how i felt on valentines day. i saw her that morning. she asked if i was going to sadies. i said, "not at the moment, but if i get a reason, i will." She then said, "well i dont have a reason either. its not like im going to dance or anything." later that day, when i was going to tell her i liked her, i was crushed, when i saw her with another guy. the only thing was, she still refered to me as her husbund, an hour later, when i saw her again. i never got to tell her. i almost did near the end of that term, but something always kept getting in the way when i tried. now, its a new term. i never see her any more. when i do "see" her, its just a casual glance as i p by. we dont talk anymore. i still like her, but after spring break, not to the extent that i did (and i feel bad about it). i guess i just accedentally drowned out my feelings for her, withought realizing it. what should i do? i still want to like her, but i only have 1/4 of the feelings i did.