Hi and welcome. I am so sorry for what brings you here. Cheating is so painful. How long has it been since you were in the hospital? Other than here, what sort of support system do you have?
We can support you as you navigate your way to your own decision about whether or not to stay with him. No one here can make the choice for you but we can certainly help you think things through.
I am tired of waiting and wondering if ultimatums work with BPs? So far the fear of me leaving has not helped jar his memory at all.
I would not recommend using ultimatums as a way to get another person to change or see things a certain way. If you want to say that cheating is a deal breaker and you will leave, only say it if you will actually follow through on it. Ultimatums like that generally do not go any where good in terms of trying to reconcile.
What are you trying to jar his memory of?
Keep sharing with us and we can help you work things through in your own head.