The first time I tried to kiss a girl I had just met earlier that night was in 2012, and I had to drink so much my head was spinning but I constantly told myself to push my limits. I told her "wanna do something crazy?" and so she smiled back at me, and I went for a kiss...
She moved her head back and I was shocked at first, but the thrill of it numbed the pain of rejection in the moment.
Nowadays, if I see that a girl has puppy eyes, and I feel that we instantly "connect" as I approach her, I can kiss her before talking to her. But I don't see it as a big deal anymore, I actually enjoy the tension, and teasing girls, and I prefer to kiss them when we are somewhere we can escalate. So to answer your question, I overcame it by blunt force, repetition and desensitization, just like approach anxiety. Oh and if a girl refuses to kiss me even at home (happened 1 or 2 times), I feel good for having taken action and know that it wasn't going anywhere to begin with or if she's shy, try again later.