You've got many options and what you do will depend on how you want your life to continue hence forth (with him, without him or with him as long as he is able and willing to correct his behavior)
Try to find out as much as you can- is he using drugs, does he have a history of mood disorder ex: bipolar/depression) is married/separated and is still seeing that person, etc.
From what you've shared, you've already expressed your concern to him and on his end, "there is never an apology and it keeps happening."
Be honest with yourself by figuring out- do you want to have the next 18+ months proceed in the same fashion, do you believe that he can correct this on his end, do you want more from a relationship than you're getting at this stage in your life, what are you willing to do to get what you deserve and want?
You are only in control of your reaction and your own feelings and actions. He is in charge of his. If you do not think that he can work together as a team in this relationship, perhaps 18 months is enough of invested time and effort on your part.