First you need to let him get over "Y", obviously he has some real deep issues when it comes to her. You want him to be over her, so he can proceed in a healthier relationship, ie. YOU. Id give him some time to get over her. The last thing you want to do is be the rebound girl. Be there for him as a friend, like you have been in the past. But start to drop some hints to him, flirt with him a little and see how he responds to you. You could also take the chance and tell him flat out how you feel, but be prepared either way in how he reacts.

Personally, Id wait a bit before spilling the beans. Make damn sure she's out of the picture and out of his heart. And in the meantime, be there for him, and maybe suggest hanging out a bit more!

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