whoa... infatuation is spelled with an "I'.
ok, now to what's more important. first, did you confront her.. (of course you did) and how did it go?? was there a fight in which she said that she didn't have feelings for you, or was she apologetic. that will come into play because if she doesn't care for you anymore, it's only a matter of time before a divorce is underway. if she is sorry and wants to try to work things out, then that's another matter. if so... this crush might be a phase or it might relapse, it more so depends on where she wants to take it from there.
for now, i would suggest that you talk to her to get more insight as to how she feels about you. don't do anything rash, yet be specific and tell her how you feel. i'm guessing that you still want to be with her, so ask her to get rid of the webcam to help smother the temptation. also talk to your brother in law and be manly about it. if it helps, ask the family to get involved so that this kinda shit won't happen again.
raverboy
...this is just my perspective on the situation...