Books I've Read: The Superior Man, NMMNG, and now reading WISNIFG

Context: I've been an avid marijuana smoker for the last 5-6 years, it helps my anxiety and some back pain but it hasn't been prescribed to me. I don't let it affect my work, personal projects, or gym activity. Since the beginning of living together (3 years ago) my wife would bitch about how it smells on me, how my breath smells, and that when I'm high she can tell with my erection. I did it anyway until she got pregnant earlier this year. I felt like I needed to be a sober father. We lost the baby 2 months ago and I regressed to secretly smoking when she's not around cause I didn't feel like dealing with her constant complaints about it. In these two months, she couldn't tell once that I smoked or even smelt it on me. A few days ago she found out and got angry that I was hiding things from her. At that point, I went full STFU mode because I was mad at myself for being controlled like that. We're not talking to each other much but it doesn't bother me.

We have a couples therapy session scheduled on Saturday and I don't know if explaining how I feel would be counterproductive, even with a therapist. Should I stay in STFU mode or try to make the most out of this therapy session?