Whishful, you don't have to make a decision tonight. You are stunned and unprepared for this shock. First get some sleep. Like Lexie said, say you won't even discuss this right now.
Get to an alanon meeting--with the baby. Begin making a plan. Realize that you have more strength than you have ever realized and you WILL live through this. You can come out on the other side of this.
Hang on to the serenity prayer, right now.
dandylion