Sorry I got back to you so late, but I've thought about it and tried to figure out what to tell you. I was at a really bad point very recently as well, so obviously I'm trying to make sure you hear the things you need to hear. The stuff is just stuff. As someone who spends a lot on material items, I understand the slight frustration, but like you said- they can be replaced and truthfully material items don't mean anything at all.
In terms of your relationship, I think it's important now not to canonize her. I know you said she wasn't a saint, but if you actually remind yourself that she is a human being that you didn't come into life with, it will help you immensely. Things I would suggest is to immediately stop checking her social media, remove her from any favorites on your phone, anything that will make her visible to you- for now. I'll explain. I have never been cheated on. Never ever. And as such I can't tell you exactly how she feels. But I do know that us women have a really forgiving nature- at least when we're in touch with our nature. It's why there's a lot of things we can't see in this world and I feel like you're not going to understand what I mean here, but just know the same way we defy logic in other ways, we operate on the heart and that's going to be the saving grace in this situation.
Her telling you not to contact her is the defense shield your infidelity has caused. Logic is telling her to have you stay away from her. Emotion is why she wrecked your stuff. Honestly, that's a good sign for you. Because that kind of response is a purely emotional one, which bodes better for you than if she just walked out. Take that as a sign that this isn't the last time you'll be speaking to her. But, the best thing at this time is No Contact. Give it some weeks, so that when you actually do reach out to her, she'll be curious as to what it is you want to say. Because in this situation, the dust will have settled and she will now likely want to know why you did what you did. Until then, find other things to busy yourself with. Just remember to remove anything that reminds you of her from your vision, and make sure when you do contact her, you make it count. If she loves you, honestly loves you, the least she'll do is hear you out.
And remember, we're human and we do the best we can. We're flawed, but we do try. And that in itself is worth reminding yourself of. Don't beat yourself up too much about it.
I hope you found even a bit of my long winded essay useful.