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If you've told your friend how you feel, you might as well clue him in too. While sometimes a crush consists of flirting and subtle hints, it will make the situation easier on everyone if you know where your crush stands. For example, there's no need to do damage control on your friendship if you discover he likes someone else! Once both of your feelings are out in the open, you are able to decide how to proceed. In other words, don't betray your friend by blabbing to your crush about her. She may like him and she may be hurt but that doesn't mean he needs to know that. Talk to your crush about your own feelings, and let your friend keep hers private if she wishes. Your friend will be hurt and embarrassed if she discovers you've been airing her dirty laundry to a boy she has feelings for. A good rule of thumb is to simply speak for yourself. Talk only about your own feelings and desires, not anyone else's. If the feelings are mutual and you want to proceed with a relationship, take your time. Let your friend adjust to the idea of you two being together before you change your Facebook status and start bringing him as a date to everything. A slow and steady start can make for a healthy, solid relationship, too. That doesn't mean you need to lie to your friend and pretend that things aren't happening with your crush. It just means letting her cope with the situation at a slower pace. If your crush doesn't respect or understand your need to take things slowly, he may not be the right guy for you after all.
Tell your crush your feelings. Keep the situation with your friend private. Take things slow.