Is it normal to feel unlovable?

So basically, my whole life I've wanted a relationship, but no girl has ever gone for me. I always like to think I treat girls right, like I'll always be there for them, offer a shoulder to cry on etc, but if I find a girl that I'm starting to like, I just get put in the friend zone! Like all my mates are dicks to girls, but still have better luck than me...
I'm a pretty normal guy too, like I wouldn't say I'm a 10/10, but I'm not really ugly either and over time I'm just starting to feel that no girl will ever love me.

(Any advice is appreciated)