Oh my. Freud would have a field trip with this!
I think it's hard to offer any kind of interpretation without knowing any of the back story..So try analysing it in relation to what happened between you two? Perhaps the ash stands for something broken, or sth faulty about your relationship that couldn't be repaired, and you were trying to figure out who was to be blamed the most? But in the end it didn't matter? I'm talking off my head here, you're probably the best one to make sense of it!