i have a solution for your problem .....!!!!
1.make sure that u r not following those stories,they really have strong impact.
2.ask your bhabhi to stay away from you,and not to talk vt you,if she asks the reason ,say what u r feeling about her,then,for sure,she herself will avoid you.
3.ask for her sorry,and dont talk to her again,and you yourself get immersed in some work,if you stay idle,your dirty thoughts will be projected this way...!!!
but am sure,you can easily come out of this,...!!!!
if this didnot work,then you urself find a girl....!!for you,she vl take care of you,.but,dont break ur family ,coz of ur silliness,dude u r just 19,teenager....!!!!ok.....!!!long way to go,why do u want to ruin ur life,just for sex...???shut ur mind from those thoughts,...!!!!