Get a Lawyer or do it the easy way?

Married for 22 years 2 children 12 & 15. Husband asked me to quit my job 2 months ago so we could spend more time together. Thought all was well had many romantic times etc...then found out he was having an online affair it had been going on for 7 months with an old jr high school girlfriend. He told me he spent 3 days with her on his vacation. He told me she was his soul-mate and that he loved her. I told him to move out. We talked about divorce and decided on a few things non contested divorce no atty. Girls reside 50/50. He agreed to pay all household bills and mortgage on home I live in, and 200 a week expenses. We own a 4plex and a single family rental. we agreed to sell all property after 5 years and split profit. He has a very successful 100k + per yr sales job. I dont want to be spiteful just want what is fair.