This rings so many alarm bells! Instead of pretending to yourself nobody will find out, you need to face up to a potential worst case scenario. How will your husband react if he finds out? How will the man's wife react? Will your husband divorce you? Will your family be disgusted with you? Will the other man's wife feel vengeful enough to make trouble for you? How will you feel when the man dumps you?If you can genuinely say you do not care about any damage an affair may cause, go ahead. If you care about any of it, you need to work harder on your relationship with your husband. He may need medical help with his libido or your both may need relationship help from a counsellor. Think long term, talk again to your husband, in a matter of fact way (no dramatics, imagine you are a counsellor!), about a possible way forward for both of you. Good luck.