We cannot get along

My husband and I have been married for 2 years and have 2 children. We have been married longer than we have dated, and butted heads from the beginning. In this marriage I’ve caught him masterbating to porn, having text conversations with prostitutes, lying, having FB conversations that are not appropriate for a married person, he locks the bathroom door and masterbates, and I’m tired. We fuss on a daily basis and things get thrown often. I opened my heart to marry him and it has slowly started to close. He sleeps on the couch and gives at least 15 excuses why. I tell him how I feel but it seems pointless. I want my marriage to work but I have trust issues with him now, frustration, and just anger. So what do I do? I have suggested therapy but that gets no response. I’m sad and tired.