You’re right that pursuing this guy whom your friend has expressed feelings for will likely damage — and perhaps even ruin — your friendship with her, so you have to make some decisions. First, is this guy worth that risk? How would damaging this particular friendship affect the relationships you have with mutual friends? You say that you all hang out in the same group, so how do you think your pursuing/dating this guy would affect the group dynamic? It may not be just this one friend you lose. You could very well lose this particular social circle altogether if your mutual friends side with the girl being “betrayed” by you. Is that risk worth it to you?
Beyond the risk of potentially losing some friends, there’s the very real risk of hurting someone you care about which, if you’re a decent person, should be a risk that rattles you at least a little bit. It would be one thing if you and she met this guy at the same time and both developed crushes on him and he chose you. It still may not be an ideal situation, but there wouldn’t be such a sense of betrayal. Calling “dibs” on someone you’ve both just met is childish. But it’s different that she knew him first and introduced you two and let you know from the get-go that she had feelings for him. There’s something back-stabbing about going for him when you know how she feels.
The good news is that feelings are fluid, and she will probably move on eventually, especially since she knows he likes you. If you can wait it out, maybe timing for a potential relationship between you will be better in a few months. Maybe she’ll start dating someone else, or she’ll get bored with her unrequited crush. Maybe, knowing how he feels about you, she’ll even broach the topic of you dating him, at which time, you can better gauge what her reaction to that would be. If it comes to that — if she suggests that you’d make a good couple, or asks how you feel about him — I’d play it coy. Don’t come right out and confess your crush, but instead say something open-ended and noncommittal like, “Well, he is cute…” and pay attention to her response.
Of course, if you decide to wait a few months to see if your friend’s feelings change, there’s a good chance that your feelings and the guy’s feelings may change, too. Maybe he’ll find someone else who is more available to him. Maybe you’ll find someone who poses less threat to your friendships. These are all things to consider as you make a decision. But if I had to give you a single line of advice or piece of wisdom to help you along, it would be this: it may take lots of false starts and broken hearts before you find your great love, but quality friendships keep you centered during the search.
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