I've been meaning to say this for weeks now, but I don't know if anyone on this board has a friend in a very tumultuous relationship. I'm in my 20s and it's not uncommon for people in my age group (and people both older and younger!) to be addicted to the ups and downs. 15+ unanswered calls during a fight might be a weekly occurrence. A "breakup" where one partner blocks the other's calls and disappears for a day or two might happen once a month, sometimes more.
With this experience, CM's interactions or attempts at interaction with the BF aren't all that shocking to me. Neither is the wait to file a MP report. Leaving the dog is a bit hinky, but if this was a dramatic relationship she may have left the dog every couple of weeks to go stay with family or friends. I'm not saying that this was the case, and I'm certainly not trying to make any assumptions about the players. All I'm saying is that it is possible that the fight etc was a regular occurrence.