My first wife cheated on me just months after we married.
When she came back from a trip with a love bite, I went through her phone (sorry not sorry) and found out; there were no signs of shame in their follow up messages, just flirting and joking.

She told me I wasn't trying hard enough, that I didn't appreciate her. She continued brazenly flirting with the guy online for weeks and showed no signs of guilt; yet I blamed myself for everything, telling her I didn't deserve her and that she was a perfect wife.
It was only when I got back on anti-depressants that I started having the strength to stand up for myself and push her away.

She's messaged me multiple times saying she still cares and wants to hang out; but how could I want to be friends with someone who'd do that to me? I adored her and wanted to spend the rest of my life with her once, but now I want nothing to do with her.

Now, family aside, I'm alone; and my self esteem has never been lower. But I'm sick of being in this rut and looking for a way out.