Oh my god I thought I was the only one who struggles with Limerance and usually at the sight of the first good looking man!
Is it an INTJ thing? It's annoying. I've only managed to destroy it once my lapse of reality is has burst. Usually I spend a few weeks day dreaming like crazy about them and I know it's completely irrational, but I can't do anything about it.
Then something will happen and it's like the biggest slap in the face ever and the limerance ends. For some people it just never goes away...a certain person I've known for about 4 years... Rejection is difficult (particularly for INTJ's who only spend their time on people who deserve to know about them) so talking to the person doesn't always work.
I find I just have to ride it out and wait for that slap in the face. =/