What does he mean by all of this?

I won't use his name so the guy in question shall be called 'Bob'. So a couple of months ago on a school camping trip, Bob decided to flirt with me, and somehow in the end, during the night, he managed to make out with me (I was slightly tired). Bob has been my best mate since I started this school 3 years ago. We're really close, he knows a lot of my secrets, and seeing as I was half asleep and managed to allow him to kiss me and what not on the trip, suddenly wondered if he was either being a player, actually half-tired like me and wanted some 'company', or actually was, you know, liking me. I decided to let it pass seeing as rumors were spreading of how we did more than kissing in the tent, and we kind of slowly drifted apart (-ish). Slowly but surely, he started to be a bit of a player, and so slowly, knowing he was being more comfortable around other girls, thought it would be safe for me to be friends with him. He thought the same, and we were friends again. But then the school was planning a Paris trip, and bob started to text me about the camp out and how he had fun and how, what about paris? foolishly I played around a bit saying yeah sure, cus tbh, he was a good kisser, a close friend, and I didn't know if it was actually 'something good' between us. So in the Paris trip, amazingly I got asked out by this other guy, who's lovely and sweet. Bob found out, and acted extremely 'friendly' towards me, smiling, hugging, high-fiving me constantly and I thought everything was cool between us. But now we have the second camp out coming in a few weeks and I'm a bit worried. Mostly because its two nights, so twice as many things could happen, and mostly because I'm worried I'll fall for bob again, even when I have boyfriend. You know when you have a good connection with somebody, good laughs, personality and you like their looks? Times it by ten, add a boyfriend into the equation, some flirty texts and emails too, and then another two nights in a tent on a cam pout with no teachers this time and no supervision? Well what do you do ... Normally I'd be faithful and stick with my guy, but he's not perfect, and bob kinda is, and I know it's a risk but I have a feeling I've fallen for the wrong person. Any advice, or similar problems experienced would be nice to know....