Sometimes i refuse sex just so that i don't seem too desperate for it

It kinda hurts my self-esteem the way I desire sex more than my partner, I'll try to initiate sex but she'll flat out refuse. I feel rejected by my own girlfriend, the same kind of rejection I used to feel when I was single trying to hook up with random strangers. It makes it clear that she's the more desirable one in the relationship, and that I just have to take what I can get. I know she doesn't mean anything like that, she's not doing it as some kind of power move, she's not a bitch, but even so that's how it makes me feel. So I've stopped asking for sex as often now in order not to seem desperate, and even once or twice I've refused her when she tried to initiate it, even though I did still want it. I never refused her in a mean way though, I used the same reasons she normally uses, that I'm not in the mood or I'm too tired. I never did it out of spite or revenge either, I never took pleasure in it, if anything I felt mean doing it. I just don't want to seem like some pathetic horny teenager to her, I want her to respect me. I want to level the power dynamics in the relationship. I also don't want to feel desperate or pathetic, I want to boost my own self-esteem.