If you fall in love with someone that you should not have, should you feel bad about the fact that you can't stop loving them?

I currently am in love with this guy (okay really smitten). And although I am 95% certain he is not married, until I know for certain I am agonizing over the possibility. My question is, how guilty should one feel if one cannot turn off one’s feelings for someone, even if they are taken. And I’m not talking about acting on my feelings, if it turns out their unavailable, but I don’t see how I could ever stop feeling the way I do about them…it just doesn’t seem conceivable to turn off my feelings. I guess I’m wondering, (and from a Christian perspective too), if it’s wrong to love someone who’s married, if one never acts on it…