Oh man, contemplating leaving my fiancé 32F 33M

Would it be rude of me to leave my fiancé of 16 years together? He is the most wonderful guy. But our lives have had nothing happen in the last 16 years…he can barely keep a job longer than 6 months and I’ve been a healthcare worker for 12 years straight. I’ve only ever been with him. He has insecurities that he needs to work on, anger problems that arise out of no where and give me crippling anxiety, and we have a dog that I don’t want to let go of. I feel bad cause yes he has family to stay with until he gets on his feet but I would break his heart. He says “you make a broke guy feel rich” like…..how do I respond to that? I’m currently in therapy and it’s giving me my life back. I feel powerful and full of confidence again. He’s always so supportive of me in what I need or want to do. I just can’t shake the feeling of now being “unequal” in our relationship. I need someone confident, or who will challenge me. It’s going to take so long to leave cause of our history but it’s gonna happen. I have tunnel vision of taking care of myself so deeply and love her first. When we got engaged in 2023 his family barely seemed happy for us so I’ve not planned a wedding, or even care for a wedding shower or bachelorette. When he drinks, he goes nuts. I’ll leave that to your imagination. I just can’t help but think it everyday and how I would do it. I owe him some money to his line of credit so essentially I’m going to get a loan to pay that down before I leave. No kids, no marriage holding me back. It’s not like I’m leaving for someone else either!! It’s just for finding myself. I don’t mind getting a small apartment but I wouldn’t be able to bring my dog with me as she’s 80lbs, I would leave everything behind. Is it worth it? He’s good to me when he’s good but now am taking anxiety meds from it because I don’t know how his moods will be like when he comes home from work. Any advice is welcome. Tia.