Really feeling for you, I am in the same position. DH left me for his mistress - the "love of his life" on 2nd Jan, even knowing she didn't really want him (as soon as he told her he'd left me she told him to sling his hook!). He then started shagging his sister's best friend three weeks later.
I received a nasty letter from his solicitor yesterday accusing me of derogatory and defamatory comments on Facebook (told my friends what he had called me - a worthless piece of shit - he has NO access to my Facebook a/c due to my privacy settings, so is obviously searching me and my DD out on there), plus emails to 'friends and associates'; the emails are to people who continually email me at the old email address (he can't be bothered to let everyone know his new email addy) so I tell them he's no longer living here, left me for his first mistress and now parading around with mistress no. 2).
I hate that man so much - and sadly so does my daughter. She's 17. We had our first mediation session Thurdsay and my 17yo DD surprised me with an open letter she'd written to him telling him exactly what she thinks of him. He has no contact other than a pitiful text asking how she is each week. She refuses to answer, so he's resorting to these sorts of tactics now. Really helps to endear himself to his daughter,
I was in a really, really bad way this morning because of this, but I am blessed with wonderful friends who are there for me when I need them and talk me out of doing all sorts of silly things.
I can't answer how you get over loving someone for 22 years - I simply don't know an easy answer, but time IS helping, if only in little ways.
He will not beat me. (one day I'm going to say that and mean it )
Keep yourself busy - it's a huge help.
Big hug to you, the pain is just so awful, isn't it.