How much of this doubt is normal and when can I settle on a decision (to marry/not to marry) that I can be sure about?
Answer: What were these mistakes, how often does he take his frustrations out on you, and, this will sound odd, how charismatic is he? The fact that you want out when you're alone and want him when you're with him suggests your brain is telling you no and your emotions are telling you yes. That says you need to ask yourself whether he's manipulative, you're impulsive/ impressionable, or both. Is he at his best when you're just about to leave?
I could be way off, but if I am, then you lose nothing by weighing the possibility that you're repelled by the reality but sucked in by the charm.
Comment: How about couples counseling together? Always a good investment.
A: Or a good premarital workshop, which can be as or more productive than counseling, though each is only as good as the open-mindedness and work ethic you bring to it.
Comment: Why does it matter if it was in front of the mother or not? This whole question reeks of this guy not being a good guy and her trying to polish him up. If someone takes frustrations out on you, why would you need to hide this from your mother?
A: I can sympathize with wanting arguments to be saved for later, in private - but, yes to the possible red flag of wanting that for the sole purpose of keeping up appearances, thanks.
Comment: This sounds totally off to me. Sounds like he cheated and now you consider it a prize that he's "picked" you for marriage. When your internal voice tells you something, you need to listen.
A: Amen. Even if cheating wasn't the nature of the past mistakes, you're onto something with the "prize" idea: It's a common mistake to link a relationship with a sense of accomplishment, be it to check off a life-goal box, or to "win" an elusive person's affection, or elevate someone out of a personal struggle, or bring out someone's "potential," or to prove that you did pick a good one, etc.
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