Sincere question: what is your IQ?
Leave child support out of it. It will be adjusted every year.
OK this is was a bit harsh.
Divorce is a financial disaster for everyone involved. Downgrades happen regularly. Your kids don't get the same lifestyle, that is for the super rich. Nothing wrong with living in a small townhouse. Rebuild.
Free (worthless?) advice. Don't try and live up to the expectations of your friends divorces; that isn't happening
Your friends may have done well in their divorces because they divorced more amicably or they had something on their exes; they didn't divorce your ex. Maybe theirs had higher incomes, maybe they are not telling you the truth.
Your ex hates you
He doesn't remember or care that you are the mother of their children. He doesn't care that you once loved each other if you ever did.
He hates you. If you were drowning he would offer you a glass of water then visit your grave and piss on it. That is what you have to accept here, you have no leverage.
You made mistakes, big ones
I said it before and I will say it again. Beg for forgiveness and settle. If you can't have him show pity to get what you want still settle. This is killing you and you should move on.
You may have to ditch your friends
Just saying, they may make you feel bad. You will find new ones.
Go with a good lawyers advice, don't be greedy, they will get more of your money if they think they can get it. You might need a new lawyer with a limited retainer...just ask them to review the agreement and ask them if it is fair. I may know a couple, someone else may too...you need the collaborative "lets not fight" lawyer.
Just saying.