I don’t think the ml person that is he interested love the crazy blonde dude as family , I don’t think the crazy dude and the ml love interest shouldn’t be together cause obviously there relationship has become toxic for the both of them and the love interest has overgrown the crazy dude. I understand the hardships they been through together but I don’t think the love interest should needs to be in a romantic relationship with him, he obviously doesn’t want to be in a relationship with him but he seems to think he owes him one. It’s painful to see him in the same toxic cycle with the crazy dude. I do think the ml lead would introduce him to a healthier relationship, it just depends on wethter the love interest is willingly to let go the of toxicity from the crazy dude, they’re literally just trauma bonding.