Sorry, but I think your thread is locked, I couldn't reply to it. So, here's my synopsis of it all:
I'll probably be the only person to back you up - you should have walked away in the beginning. I am with you on not wanting to continue the R while she was pregnant with her boyfriend's child. Major red flag!!! However, it seems a little strange she didn't tell you until 3 mos. later. Not in this day and age. One month, okay, but by the second she knew. It seems she panicked when you were going to pull away. Assuming - you had long talks about choices; it was her decision and hers alone to put the child up for adoption. Where was the father? Did she even tell him? It s/b between him and her. You did nothing wrong, as far as I can tell.
Should you have been more empathetic towards her? Yes. That was a difficult thing to do. The child is in a very loving home now, that's the bottom line. She'll never forget what she did. That's understandable.
But...it seems like your R was built on lies from day 1. Could it have been your child?
My concern, is that she seems, to be playing Leap Frog with men - always searching for someone else to relieve her of her own unhappiness. That said, I would add, also that you both probably never really loved each other from the "get-go".
Jump to now - You both have a child together, the M is extremely rocky, she's unhappy, and you're unhappy.
Do follow all of the DB principles, stay with your C and if you can, keep talking to the DB coach. They will help you a lot.
Finances - Tighten up the checkbook i.e. have money for all household expenditures, but open up a savings acct. that neither one touches, also start a college fund for your son. Let there be just enough left to tide you over for the rest of the month. This has to be done with an honest sit down talk, about saving money for the future. Don't talk anything near the R route.
Let her know, you are very serious about this.
You know about your anger (stop) how to do 180's etc. The Om, you know, not to focus on - just focus on you and your son. Why didn't she go with you to see your parents?
Yes, she is squalling away money for something...not a good sign.
Yes, she feels awful about the adoption choice, but I will assume you did not push her into it. She has more on her mind right now, beides the adoption...keep your eyes open.
Continue to work on the areas that she pointed out to you in the beginning - that she feels that drove her away from you mentally.
Empathize, listen, empathize, listen, etc.
Be nice, sweet, don't argue...she doesn't need that right now.
Let me know how things go...but, keep your eyes open, or she may leap again...
Good luck...I hope this helps a little. My opinion only.