After 14 months of dating I told my BF "not sure if we're on the same page- you haven't said 'I love you' back and I don't know if you really want the kind of future, marriage kids etc, that I do." He said "I love you and I will marry you when I decide the time is right." I gave him a big hug, then he knew I had plans w my best friend. Well, he tried to meet this single girl alone at a bar at midnight (she couldn't make it). He'd told me nothing about her, saved her as a guy's name in his phone, later deleted the tects. He spent the whole next week (while I thought we were fine) flirting w her, asking her for pics. Months later a text from her popped up on his iPad asking if he would come over her apt and drink with her once she's back in town. My BF responded "definitely!" Well I think this made me feel insecure & I also felt weird that he refused to have any sort of future discussions - I'd say "so do you plan on us getting engaged within the next couple of years or so?" And he'd respond "I'll let you know whenever I'm ready, if that's not good enough then you're an adult and you're free to leave." Then he said "I'm warning you, the more you ask me about marriage the further away it'll become, and eventually I'll leave."
Now we're broken up and he said on the phone "i miss you but I warned you I'd pass the point of no return, & also how can you pretend you've changed, you're not going to stop asking me about marriage." I said "so you're happy with just never seeing or talking to me again?" He responded w silence which is always his go-to. My question is, how can I possibly convince him that I've learned my lesson and being with him is more than good enough now?