My husband and I had not been living together for 4 months

I'm sorry to hear that you are going through this. It is really never easy for us women. Especially if kids are involved. If you are seriously considering a divorce, you have to think of your support network cos u have a baby and a toddler. It is not going to be easy being a single mother. You got to be real strong and I really hope you have family by your side who supports your decision and is able to help you in your road ahead. I wish I can say your hubby may change and to give him a chance but I agree when people say once a cheater always a cheater. Think this through very carefully. I too have gone through a divorce and it's really not easy. Hugs frm a concerned mummy. :)