I second CW... and was going to recommend not necessarily writing it convincingly, but letting all that anger out. You can write as many letters as you want! Just don't send them.
Do something physical too if that helps-- even just a short run (or a whole bunch of jumping jacks!) can clear your mind a bit. I got a punching bag and it was amazing for getting out the anger and a bit of a workout without even noticing it at the same time.
Hang in there. xx
Me (46) H (42) M:14 T:18, D9 & D11 4/19 - 12/19: series of escalating BDs 9/20 - present: R and piecing
