I'm heading for my sweetest, bitterest downfall.
Tell me what you mean by that.
The other day during our weekly grocery shopping, my boyfriend came home with a tub of ice cream, and while we were eating it, he started his long rambling about this and that and then we started discussing why we should never watch the same movies and then I wondered if we should ever be open about our love and all that and then we went to bed and the next morning he told me he kissed his ex-girlfriend.
Your guy made a mistake when he kissed his ex-girlfriend. It's basically cheating, therefore I completely understand if you're upset and want to end the relationship.
It doesn't matter to me anymore. I've already deleted his contact and blocked him.
Sounds like a good course of action. That's what I would have done. I think you are very mature about this, and I like how you cut him out completely to avoid any unnecessary back and forth.