<human>: Alright,

Background:

Me and my girlfriend are both 18. We are in our final year, Grade 12, of high school. We've only been going out for about 2 months but we're quite close I think.

Basically, she is extremely self concious about her weight, and always has been. She does not want to be fat, ever. Recently she had been eating unhealthily but I convinced her to start eating 3 square meals a day at least.

But yesterday she said to me she has been putting on weight (which I expected) and it's stressing her out and making her unhappy.

We have our matric dance (prom to you Americans) in 2 months (she's my date obviously) and she wants to look as good as possible. Unfortunately, this means losing as much weight as possible. 

She's said to me she's going on a strict diet (which means not really eating much at all) and that she has made herself sick in the past in order to lose weight, which she said she probably will be doing closer to the dance. She hides it from her parents by running a bath while she does it. She said her parents have caught her doing it before and they got angry. 

I told her I don't care if she hates me, I will tell them. She told me if I do it will ruin us because **she won't be able to trust me or anyone again** and she has had trust issues in the past.

Now I really don't know what to do. I'm scared. I feel like a bad boyfriend.

She said she will be able to control it and that I mustn't worry but I obviously know life doesn't work like that; one minute you're in control, the next, you're not. And you don't even realize it.

Please help me.

Can you give me a shortened version of the text?
<bot>: (I'd really appreciate it if you read the whole thing) girlfriend is starving herself and I'm the only one who knows and I'm completely lost, help me please.