Well I personally don’t care how long he’s been cheating. A week or a year. He is cheating on his spouse. Ending it immediately is not too fast. Why do you think you need to wait? Unless you want to be married to a cheater (make sure you never have sex with him though as it will take one time to get STD including HIV since who knows who he might have sex with besides you).

If you are dependent on him, take steps to become self sufficient independent woman so you aren’t limited in your options and aren’t forced to stay with a cheater because you can’t pay bills on your own. Make your self sufficiency your life priority. If you plan on staying together, insist on regular STDs tests. Your health is in jeopardy and he can not be trusted.