Cheated

So me and boyfriend have been together for about 8 months. Were not having sex at all. Also were both in high school. He's had sex before but I have not. So this past weekend he tells me that he almost slept with another girl. He told me that he grabbed her ass and thighs. I'm sure they kissed and did other things but he won't admit to it. Well I'm in no rush to have sex and I do love him but I feel like if I don't put out he's going to do this again. And idk if I really want to put myself through this again. I just need advice on what to do