Im a biual and badly need advice on another girl,is she playing me or am i in the wrong?

im a 24 yr old .i no this girl who is related to my sis in law for a couple years, we have meet a family gathering etc just didnt get to no each other to well til i asked for her numb for the crack. I txtd n from there got to no eacother better wit harmless flirtin from that and fbook thinkin nothin of it. few weeks past and at another family gatherin i asked her to call over to mine 4 a drink later if liked, so she did. after a few drinks she just kissed me out of the blue,nothin more, we drank all nit, next mornin we kissed again and den said tat it cant happen again. few weeks ped with the odd txt, she was vistin fam& i convincered her again to call over to have a drink wit me n my best mate who is also gay but lik a sis 2 me..same thing happened again, but she chated with my best f mmore as.they chated bout wer she from as my mate was plannin 2 movewer she lives 4 college, so they joked bout movin 2gethr as she needed roomate,i was drunk and stupidly accused them of flirtin..few days later we all went out as family gatherin and i got in fight wit my friend as the girl i lik was hangin with her n smokin 2 gethr, even doh my mate dont smoke and exnoring me. i apoligised seperatly to them next day for my part, i was just afraid my sis in law wud find out we kissed and hate me,so the story now few weeks later is.. my best f moved there,now there roomates.me and my best mate dont really talk now as im hurt bcus she new i liked this girl& made me luk a stalker n not defend me wen she of al peple nos im not lik tat so put her off me,the girl i lik she hasnt textd me since, she has bein down twice and wen i texted to ask to meet to say let forget everythin n start fresh as friends she stil dont reply, last week was first time i heard from her, when i textd sayin let just start fresh as mates& 4get we kissed. she replies hi busy with studies another time,so a family event is comin up and my best mate and the girl i lik wil b there and i dunno what to do, am i bein made a fool, act like i dont giv a ***, or dress up y and play her game? but i dont wanna hurt my sis in law 2 as i care more about her, help me wit this DRAMA !! cheers