Constant thoughts of wanting to cheat on my husband

Obviously I’m not going to do it. We haven’t had sex in 3 weeks and it’s always completely unsatisfying for me. I’m continuously having fantasies of being with other men, finding myself having little crushes on the men around me. Theres no passion in our relationship we’ve been together almost 9 years married 3 and I just feel like we have grown into different people. I know I should talk to him but it will do no good. He will just want to argue, call me names, blame everything on me so I would rather just continue feeling this way quietly. It goes away eventually but always comes back