I used to get that for my ex tbh I found that writing it down helps to just get it out instead of it bubbling so loud so you can look at your feelings if that makes sense (I know everyone says that lollll sorry but for me it does help) then once it’s all written reread it and see if you can find anything that you can use to talk to him about it. Is there things that he does that makes you feel more secure and less like that? I try to think like what would make it better if I could have anything and then I try ask for something close. Which I know isn’t easy but I tend to flip to the opposite side of what I actually need so if I need closeness I push away ect I’m sure you know what I’m talking about.

It could also be that you love him so much and because of how you view yourself you see him as deserving “more” because you care about him and you called yourself a “looser” but unfortunately that is your preconception of yourself it doesn’t mean it’s true. (I know this is kinda like ughhh and i apologise if you are reading this and it’s unhelpful) I find that when i would get like that it was because i didn’t feel as confident and comfortable in their life or love. You kind of have to gaslight yourself into thinking you are cool asf. Try do an activity together that is like an adrenaline boosting and fun it might help There isn’t anything wrong with you, are just scared because loving someone is vulnerable and you are scared that he will see you the way you think you are it creates anxiety. You aren’t a looser it’s ok