Hamster, maybe these things - apology, not dragging out every hurtful detail - could wait to be said in person? I think it's good to wait on a decision for a serious matter, and the time is still close with the incidences with the ex.

Why do you want to apologize to him right now? Sorry if i missed something, i try to keep up, but been a difficult time lately. Did he express his hurt over the past recently or bring up the subject to you? Or do you want to know right now if he will reject you so you could avoid that possible future pain?