Dear James,

Well, if you didn't know it before, you certainly do know for sure now that girls are attractive, and you find some to be especially so. You also have discovered that, despite our decisions and resolutions, we are almost defenseless against this attraction if we foster it and put ourselves in certain situations.

What is my suggestion? You are hurt and confused not because you think it was wrong in itself to kiss a girl but rather because it went against your decision for the priesthood. You kissed her because you have a crush on her, which is her effect on you due to a combination of factors that are both external (looks, etc) and internal (having to do with your personalities and values), and... you have been thinking about her. To be a celibate priest you have to put something, or rather someone else at the center of your thoughts and life. 

You can't do this on your own; it is a grace that you have to ask for and then to protect. Prayer. But don't pray for God to take away the natural attraction (that is the easy solution and one that we are more inclined to ask for) - he probably won't. Pray that he place something else alongside it in your heart and soul - love for him and for souls, which you will cultivate with his help and make grow stronger than anything else that pulls at your heart now or later. And then pray for his grace and help to be strong enough to protect your love and option for him - that you will be strong enough to forgo occasions that will put it at risk, that you will dedicate your time to doing things that will build his Kingdom, that you will be faithful to his love and your conscience when occasions arise where it would be easy to compromise.