I was in a relationship for 3 years (my first) with a guy – and I broke it off, not because I realised I was gay (that came later) but because I knew I could never love him in the way that he deserved: the way he loved me.
yet he will always be a part of me and I will always love him. I love his kindness, and intellect and his capacity for reason and his talent and his love and his thoughtfulness and so many other things. Yet despite everything I loved in him – It would never have been fair to stay. because I did not love him enough – and as I come to understand my own sexuality more and more I understand exactly how much I wasn’t able to love him – and why. He will know – and it doesn;t matter because I don’t regret our relationship for a second and I learned many things and got to know an amazing person. I will always be thankful for that.

We remain friends to this day (3 years since) and my girlfriend (my only partner since, who I got together with a fair time after the brake up) and he get along really well.
But we are not as close as I once hoped – partly because I know that the fact I am gay – and that I did not tell him: that he had to guess – really hurt him. We have never really talked it through, not like we used to talk things through when we were together so I’m not sure exactly how he feels. But despite that pain he was a true friend when I came out and supported me whole hartedly and accepted my gf as a person whom I think he has even grown to respect. He never questioned me – never asked even if I was Bi, (although many others assume that my relationship with him ‘makes’ me Bi and politically I wish I was.) because I think he knew before I did that I am gay. I hope he knows that he is special is the only man I will ever love, I loved him as a person.
He is now engaged to a woman who is perfect for him and they will have what I would never have given him – a family.

What I wanted to say is that you are not alone in your position: although you have handled it far better then many. She is very lucky indeed to have you as a friend, although i will underline another’s comment when I say that it is a good idea for space, at least temporarily until you get over her. Otherwise the pain will twist inside.

Good luck to you – and thank you for loving her so much that you are willing to loose her as a partner in order to see her happy – thank you for being her friend.