First of all, to qualify my advice, I am not suggesting you get married to him because he’s your last best chance at happiness, hell no! Better to be single than married to a turd.
What I am trying to suggest is that you think with reason - think about the positives in a potential relationship and balance it with actual negatives. Do not start to assume things about him. And also be realistic - you cannot create a perfect partner - ask all of the married guppies and guppans. Not one of them can say their partner is perfect. Every individual is flawed, you included. So then, why not think about what’s workable and what’s not workable in a relationship. Think about where and how you can compromise. One more thing, people change over time - some people get better and some don’t. You need to be prepared for you and him to change over the course of a relationship.
As for your mom not liking him, while I think moms have great intuition and I think you should hear her out. But sometimes, moms get it wrong because they’re so sure their child is going to get hurt, they don’t even let them take a chance. Listen to your mom, but make your own decision.
