There's a difference in being in love with someone and being sexually attracted to them. In this case, it sounds like you have a pretty strong sexual attraction to them. But my question is, how do you feel about them on the inside? Do you know them well, like them for their personality, the things they do and say, their values, etc., or is it just the physical attraction?
It's OK to be physically attracted to a lot of different people. Not saying it's OK to actually get physical with them, lol, but it's completely normal to be turned on by someone that you think looks attractive. I mean, hey, you're 13, your hormones are just starting to rage... there are probably going to be a lot of sexual feeings over the next few years, but there's nothing abnormal about that.
Now, since you're concerned enough to ask for help, I'm wondering what exactly you mean by what should you "do"? My advice is to just accept it, but I'm curious if you're concerned that you're going to end up doing something you'll regret..?
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*~*Luv ya, Annie*~*
*~*Live, Laugh, Love*~*