I would think that the more time you spend in a relationship with that person, the less you feel that way - if indeed you ever doubted them in the first place. You just have to accept! And really thinking that someone is only with you cause there's no one else is silly. That's taking it a bit too far. And not having the doubts should make things so much easier and blah blah blah obvious stuff

why do I feel like I'm giving you specifically advice