Hello, thank for joining me. Please forgive any typos as I get very immersed in my work with you and sometimes my brain goes faster than my fingers.
Very important for me to say this up front. I think you sound like a wonderful man, boyfriend and father and step dad of sorts to her children.
It is not uncommon when things are going so well that sensitivities creep up and a pushing away of sorts may happen. I think some of her past hurts and fears may be in play hear and she is pushing you a way a little bit in order to protect herself and her children even though you have given her no reason that you are going anywhere. The comment you made with her friends was innocent and not meant to hurt and we all as parents feel that many times. I myself often long for a day when I can be free...parenting is hard no matter how old are kids are and wanting a break sometimes ins't a bad thing nor is verbalizing it. So, let's cut you some slack there.
I would maybe sit down on the heavy conversation right now but show her the love you have for her and provide her the reassurance she may need during these moments. The intimacy will come back. She may also benefit from some counseling to help with her feelings of guilt and then maybe the two of you can go together to work on these things that have crept into your relationship from the past.
I apologize for the mistype above...I wanted to say maybe hold off on the heavy conversation for a bit.