I'm very sorry to hear this news, but I'm not the least bit surprised. Many of them want to rush a divorce because they think it's quick fix to their problems...little do they know that their problems are only just beginning once the ink is dry on the decree. Some of them are very euphoric once the divorce in finalized, but that is short lived because that new found freedom and excitement soon become dull and the day-to-day responsibilities set in.
I understand how you feel about not wanting a divorce, but if he wants a divorce, it only takes one to do so (unfortunately). I wouldn't attempt to drag it out too long because it will cost you more $$$$ by doing so. My advice is that you speak to a lawyer NOW and get your ducks in a row to see what you are entitled to. I know that I sound harsh, but knowledge is power and unless he changes his mind, he may very well go through w/it to avoid paying out more after April.
For now, I wouldn't bring this subject up w/him. Let him come to you about it. When he does talk to you, listen to what he has to say and they say "h, I'm sorry you feel this way. I'm going to need some time to come to terms w/this divorce". Then let it go, but do not tell him that you've spoken to a lawyer. That is knowledge that you keep to yourself.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.