Waheguruhelpme ji,
Please listen to a woman who is probably old enough to be your grandmother.
He is on his BEST behaviour now. It will not get better after marriage, it will get worse. If he is disrespectful of you now, it is a sure thing he will be more so after you have become his property, which is obviously how he sees you.
If you actually marry him, I hope you are able to physically defend yourself because he will almost certainly try to use physical force against you. Please take care.
Please don't believe that all men are dogs. There are some good ones out there. I was married to a very good man who would never dream of lifting a finger against his wife.
After he died, I married another man not nearly as good, but he never tried using physical force against me because he knew that doing so might prove fatal to him.
Please take care and only marry a man worthy of you.