IMHO, his behavior at the seminar and immediately afterwards was inappropriate. Lying just iced the cake.
I believe your discomfort and feelings of taking a step backwards are from your reaction to his behavior. He acted, you reacted.
Be gentle with yourself. You have been taking care of yourself and maintaining peace in your home while the divorce process continues. This situation prompted you to react instead of respond. Progress, not perfection - okay!? Don't beat yourself up over that explosion of emotions. You were being lied to (again) and it triggered you.
Keep taking care of you. We're here to support you!
hijack alert:
to hammerhead: I was reading and hoping you would throw this jewel in one more time!
BTW...(if I wasn't clear)... you might consider throwing the stbx turd to the sidewalk. 