I found an empty durex packet

I found an empty durex packet in a bag of rubbish my hubby had cleared out of his car. I’d gone to the bin to put some out myself and saw he had wrapped it really tightly so I undone it and there was another bag tightly wrapped inside and it was inside of that. The car was going in for repair so this is why he cleared it out but he’s always clearing rubbish out of his car. I confronted him and eventually he confessed. The trouble is, he says it was 4/5 years ago and it happened twice with a work colleague. The durex pack has an expiration date if March this year so I don’t know if that’s true. I have lost all trust. We have been together 21 years and have 2 children. I don’t work and would struggle financially. I’m scared to go it alone and he says he is sorry and that he doesn’t want us to split up but I don’t think I can forgive him. I don’t know what to do? I don’t want to upset the children either and I’ve been through an unbelievable amount of upset and pain the past few years and it feels like he’s kicked me whilst I’m down. Any advice.?