<human>: Give me a shortened version of the text

I've loved my mates girlfriend for the last two years and at the end of last year she revealed she likes me too, we didn't plan to act on our feelings and I feel terrible for this but we ended up sleeping together in the heat of the moment and from there our relationship got mostly sexual until a few weeks ago and I don't know what to do.

Ok so I'm 23 she's 23 and my mate/her boyfriend is 22, they've been together for almost 4 years and I've known them for 3. I've always got on really well with her and developed my feelings for her over the first year of knowing her, when i realized how I felt I tried backing off, but this did not help so I continued seeing her as a friend. 

I must have been giving off some signal that I liked her though, cause around November she revealed that she really likes me and said she knows I like her. I admitted it were true but we agreed that we would not act on our feelings cause of her boyfriend. However at the beginning of January we were alone together and messing around when we kissed and this quickly lead us to the bedroom. Neither of us really talked about this but we started sleeping together on a semi regular basis until a few weeks ago when she's suddenly become very cold.

I've asked her for the reason she's like this and she says she doesn't want her boyfriend finding out but she still wants to be with me, this is driving me mad as my feelings for her are so strong and she's on my mind so much. 

I don't know what to do from here, I have loved this girl for a long time and don't feel I can walk away because these 2 are the 2 main people in my life and if I'm going to get distance from her I also have to get distance from her boyfriend and I don't think I can deal with losing both of them. So what I want to know is what can I do, I know I'm in the wrong but I really don't want to lose her and is there any way to reduce my feelings for her so we can go back to just friends?
<bot>: Love mates gf, started sleeping with her after loving her for a year, but she has become cold towards while saying she still has feelings, what can I do?