Girlsgroup, welcome to Psych Central and hugs for all the hurt you must be feeling.

You were lied to and that must really hurt. I guess you can be thankful for one thing. You are not stuck with his baby. That poor woman he is with now may be left or cheated on. I feel your pain and her pain.

How to get through this:
Talk to your therapist or get a therapist. This can really help get to the roots of the problem.
If you find yourself getting depressed, seeing a psychiatrist and having them prescribe appropriate meds can help.
At Psych Central (PC) there are forums on Grief and Loss and other areas that may be of interest.
Psych Central - Search results for Recovering from roken relationships