Do it, because it will only get worse after you are married. He does not respect you so once you are married, and especially if you put on a little weight, then he'll be out fucking around all the time.
And if you're 18... please trust me and wait. I'm 48 and WISHED SO MUCH I could go back in time and not have gotten married at 19. I thought I was old enough and that I knew who I was and knew who I was marrying. WRONG. Our brains don't stop developing until the age of about 24, so you won't even know yourself or your partner, until you are both older.
Honey, drop this fucker like a bad transmission.
Invest in yourself.
Keep your ass in school, like some college or tech school and get a degree.
Go and see and do things, travel when you can.
Learn how to scuba dive and visit the Caribbean.
Learn how to fly a plane
Learn how to play golf (lots of deals and jobs have been made and had on the golf course).
Put off a serious relationship until your late mid-20's.
By then you will have learn quite a few things and will be better prepared for a life of marriage and the obstacles that come into that union.
Good luck babydoll.