The relationship is over . . how do I end it?

BFof 4 months disappeared twice in the past 3 wks while on a business trip. Before that we talked daily, went out every weekend. (No yet.) The day he left he was very distant & disengaged, & called me for the 1st time only 8 days later, only after I sent him a note asking what's up. He apologized profusely, said it would never happen again, asked if we could still date. I accepted his apology said I understood. But not sure about dating (I mean, how much time/effort does it take to send someone a quick text?). We talked a couple of times the following week; we were friendly but things just weren't the same. We were supposed to meet for a 3-day getaway at the end of his trip, but I asked for a rain check. That was 8 days ago. Haven't heard from him since. To me, the relationship is over. How do I make it official?