My husband, who is 32, cheated on me. If I decide to stay, would that be the wrong choice?

To make a long story short, I discovered he had been smoking weed and drinking without my knowledge. I got him into rehab, and while looking through his phone, I found evidence that he had cheated on me with a coworker. I had already printed out the divorce papers and was prepared to file at the courthouse. However, he appears to be making an effort to repair our relationship and wants to work on our marriage. I'm torn about whether to give him a second chance. Has anyone stayed in a marriage after infidelity, and did it endure? I understand the saying "once a cheater, always a cheater," but I'm curious if this marriage is worth saving and if there's a chance he won't betray my trust again. We share a daughter who is 4, along with a dog and a cat. With him in rehab, I've already lost his income and can't cover all the bills on my own. If I choose to leave, I worry about my ability to provide financially for our daughter and take care of our pets. I still love him and don't want to go through a divorce. At the same time, I'm afraid of the possibility of being hurt again by staying with him.