If you feel that he is the one then you are saying that you are willing to work on anything - even this. I actually agree with you. I don't think he was taking care of his mother and I think it was rude and inconsiderate. He should have at least made an effort which he didn't. But this can be talked about in an effort to move on. By telling him how hurt you were then you hopefully will change the way he looks at what happened. By saying nothing you make it okay to put you behind everyone else. It's okay to voice your opinion.
If you want this to work out then resolve this by talking and move on. You can have a good relationship and still talk about this. Use it as a way to move on and learn about each other. You can tell him you love him and be happy. Learn how to voice your concerns.
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