@adrienne169,
My brother did this to his first wife after 19 years of marriage and two young boys. He actually told me "I was trapped in a loveless marriage for 19 years but I've met this wonderful women". I urge you to see a lawyer, stick with a counselor to help to get ready, it's not going to be easy but you don't want to live with a man who is always seeking something just a tad better than you. Please don't let him convince you it's your fault. If you had been married 2 years and decided to split, it's probably nobody's fault, you both picked wrong. But after 16 years of marriage, it's somebody looking for a change.
Please, please, please get a handle on what assets you own together, what income is coming in and what is going out. Do a credit check to make sure there are no credit cards you are unaware of. I believe in an equitable split of assets. But find out what there is, and since you have 16 years together, you both might have a claim against each of your retirement funds. Don't sign any releases until you've. Read them 5 times and your lawyer has reviewed everything. I'm embarrassed that my brother contributed very little towards the support of his children. I wish you all the best, but please get ready. My first husband tried to make me homeless, he wanted everything, including the baby's crib....it was a nightmare.