Important question should I leave my SO!

I have been feeling like I don't want to be in my marriage anymore. For a few reasons one we been married 3 years and those 3 years have been fight after fight and he's hit me a few times, also I found hotline number on his phone bill but Now he's being nice and caring but I don't believe it one bit im waiting for the other shoe to drop and I feel like this marriage isn't working anymore... Help need advice