Is it normal to want to fuck someone else

Sounds like you are just a slut. Do you live in a trailer or mobile home?

Maybe you just don't like commitment? Maybe you are just more of a one-night-stand kind of guy and don't want to be tied down. Or maybe once you've gotten the girl you want, you just want another and can't pick just one goal and stay with it.

Variety is the spice of life.
All cunts look the same , but they all dont feel the same.

Your life is too focused on sex. Thats what the problem is. You find one pretty girl, then find a prettier girl and want to screw that one instead.

You wont be satisfied only wanting sex in a relationship.

It doesn't matter if you're male or female, you're normal. We are animals who invented the concept of relationships. We have urges and live in a sexually charged world. Just limit the cheating and lies, use protection etc. Have fun ;)

I guess the mere fact that you find someone sexually attractive is normal. But if you are in a supposedly committed relationship, and you actually want to have sex with someone else rather than just simply admiring something you like with your eyes, then yes, you have issues that need help. The inability to be faithful to your sig other will prove ruinous to your life in the long run.