My W had an R and D13 was born. I've been her dad since she was 2 and she's legally adopted. So my sitch is a little different, at least for future legal.
But I will always assert my father role with my D13. I love her like my own and will always support her, guide her, be there for her. When she has issues with her mom, I am always there to listen to her and talk to her.
It's all I can do, but I would never walk from that. No matter how I get frustrated when my W and D13's co-dependency kicks in and I just want to get out of the way as they both spew venom at me...
I would just suggest to be the best dad you can be for your SS14, unless the law says otherwise.
If not you, then your SS14 may find his support in other ways, and they might be a lot less healthy than any anger your W has with you because of the R you've formed with him.
