its the old saying, if you love something let it go, if it comes back it's yours forever, if not it was never yours to begin with.
I've been in a similar situation when I was younger. A friend told me that he had feelings for my gf. Being cocky I said he was fine to tell her. A few weeks later I found she didn't know what she was going to do about it. I told her to go with him if she had to, played the whole 'your happyness is important to me' card. I stayed freinds with my mate too until he came to me less than a year later and told me it wasn't working and he was going to break it off. I beat him senseless for putting me through that and then putting her through it but in the end she came back to me and we had a great next few years.