Sometimes I feel so pathetic when it comes to girls.
Why do you think you're unsuccessful with girls?
I have never had a girlfriend my age. People say I'm so unattractive.
Everyone lacks confidence from time to time, but you shouldn't constantly beat yourself up over things. Acknowledging your flaws and trying to improve them will make you feel better and greatly improve your confidence. It will help your mental health too!
I'm too used to the pain from being pathetic...
You're not pathetic, and one day you'll find a girl that you can really connect with. Love is hard, but keep finding and you'll get there.