I’m so sorry you’re going through this 💐
I think, if at all possible, you should get the stuff out of the recycling. Give yourself some time before doing things you can’t undo.
Feeling humiliated, embarrassed, worthless etc, it’s silly isn’t it. THEY are the ones who’s should feel like that, the ones who lie & cheat, not us. I guess it’s going to take many more generations to hopefully one day undo the absolute myth that ‘If you are slim, attractive and a ‘good wife’ your husband (partner) will be faithful, if he’s not faithful it’s your fault and you are stupid if you dont realise it’s happening. It’s so bloody ingrained you don’t even realise it. We should feel sadness and anger, not embarassment & worthlessness.
You need to tell some people close to you, they need to understand what you’re going through. Choose a couple of friends you can trust and talk to them. Then, you need to talk to your children. They’re adults now, I know he became their Dad & your instinct is probably to protect them from it, but they need your honesty & they need to understand what you’re going through - I think you will really damage your relationships with them if you don’t tell them.
I do think it’s possible to love someone very, very, much but still not be the person you should be. I think he loved you & your life together but was able to compartmentalise that & keep it separate from his relationships with others. I think his childhood was probably quite screwed up. I honestly don’t think it means your relationship/you weren’t exactly what he told you they were to him. He sounds totally screwed up, not like your regular chancer shagging anything in a skirt. I think seeing him as a damaged man who loved you very much is probably the best way to try to cope (and I feel it’s the truth).