So is this the friend of your ex (the ex from a while back who is your mate)? Or someone else?
Jesy, your posts just scream "how do I keep him happy", whoever you talk about. You need to be confident about you, your needs, and expressing those before you date.
Sometimes there are bloody big red flags waving and people can point those out, but this early on - pretty much no-one can say if he's into you or not. Hell, after 3 dates he's allowed to not know yet! So are you!
It sounds to me like you invest far too much, far too early.
Just take it more slowly.
I'm going to say don't have sex, as I do, early on. But I can see why it's a good idea to wait! But if you don't like a position, just say no - it's too early to be explaining why. I'm guessing an issue in a past relationship, and I don't think it's a good idea to show yourself as "vulnerable" so very quickly.
Same with the weight, really - a bloke you've seen a couple of times shouldn't really be your #1 weight loss supporter...
It just sounds like you make everything full on, too much too fast.
And you are scared of pushing them away... this guy, the Valentine with the other guy... You have to do what YOU want, and if it pushes them away, they are not right for you.
I has sex with my now boyfriend, and after a couple of meet ups just said "so are boyfriend / girlfriend then?". It really is that simple. If he'd wobbled on it, I'd have moved on. I'm fine with FWB in principle but it's not what I was looking for at this time in my life, or with him - so it would have been better to "scare him off".
You need to start expecting more.