Hello everyone!

I'm not sure if this is the correct board to post something like this on, but maybe it will be redirected elsewhere if I haven't chosen correctly.
My son has now been out of a relationship of 5-1/2 years with an unBPD woman. It has been three years now since the breakup. They have a child together so he unfortunately still has to have contact with her. There are notable differences in him and he is somewhat difficult at times to get along with. Are there any tips that one could give a mom who needs to know the best way to go about my relationship with him? It almost feels like I'm walking on eggshells now in not triggering him or making him mad. He is now in a new relationship and he will be having this child in November of this year. I so much want to be a part of their lives but feel actually afraid sometimes to have conversations with him. I do believe this is the aftermath, and the still ongoing, but to a much lesser extent, with his unBPD.
Any suggestions on how to handle this situation on my end? He unfortunately did not take the time after the breakup with the unBPD to go to counseling any get help.
Thanks everyone!
Angie59