I like my best friend and she knows but she has had a boyfriend for a year. I respect that so I didn't do anything about it. But as she is 17 at boarding school and he is 19 at uni they rarely get to see each other. So what I think is happening is she is using me as a sort of "temporary boyfriend" while her boyfriend is away. And so I keep taking things the wrong way and thinking maybe she likes me.

We are very close, we flirt a lot, she always gets as close as she can to me, she breaks the touch barrier every day, we always have eye contact, she is really shy but she always starts conversations with me, she always wants to know where I am and everything about me, she said I'm the only person she can trust and she was on a date with her boyfriend yesterday where I work and she kept texting me asking to go and talk to her.

I don't think she realises how much she flirts with me.

So tomorrow I have decided to tell her what is going on (because I don't think she realises). I REALLY don't want to lose her but I think I have to because if I don't stop this now, it will get out of hand. We are so close but I think that's what the problem is. Obviously I respect the fact she has a boyfriend but if there is a chance of anything happening I want to know, however I'm not going to pressure her.

Neither of us want to lose each other but if we don't have the same feelings then the situation is surely incompatible?

So I need some advice on how to handle the situation? How do I tell her that I need to be away from her? I think she will get upset and cry and that's what I really don't want to happen :(

So what if she gets upset. She is the one with a boyfriend and is flirting with you.
You need to set some boundaries if you stay friends. No flirting, no texting when she is with her boyfriend (which is very rude and selfish on her part), no touching. Seems to me she is using you for company when her boyfriend is away and that is selfish as well.

You are her boy toy, her surrogate, her spare...
You write well and sound intelligent and aware. I'm sure you will handle this, despite the way feelings can cloud anyone's sense of reason.

Do I forgive a girl who played me?

Bottom line is, she has a boyfriend and you like her other than a friend. You need to just step back. Things are always going to be strained now. Time to just walk away

She didn't play you. And there is nothing to forgive. You went along with her program and knew she had a boyfriend. You had every chance to make a better decision on YOUR actions. You still can without the extra drama, by being less available.

Relationships are usually on a sliding scale. She didn't play you by leading you to think you were about to be her one and only, but she played on your emotions by touching and 'needing' you a lot. A bit selfish. C'est la vie. We all hurt when things fail. It probably won't be the last time, with countless variations. Try to keep busy, but don't negate your hurt - two very contradictory steps, so set aside a minute each day to wallow in memories. It's OK and even a bit healthy to see her as 'having played you' just so that you are miffed enough to see her as undeserving of you, even if that's sort of untrue. That's why friends always say 'Hey forget her, she's not worth it.' It's the ritual of getting over someone.
Eventually it will fade.