You get nervous and just start blurting out obscene statements? Do you have Tourette syndrome? And I'm not joking, I'm being dead serious here.
While I don't know exactly how to help you, other than to say, seek help, I will say that at least you realize that your loss of control isn't working in your favor and not blaming other people.
Here's the thing, how about you just realize when things are getting into Incredible Hulkish for you, you just take a chill pill, time yourself out, and max and relax like you're doing it for TV.
And since I don't want you to freak anybody out, I think you need to take some time to yourself and practice some restraint. Like, you don't HAVE to make obscene comments, its just your defense mechanism...and an odd one. Especially if you like somebody. But like I said earlier, its something you can work on and maybe some professional help wouldn't be a bad idea.
Oh god I do this all the time. Whenever I like someone i just become extremely obnoxious and SCREAM things around them for like no reason.