@Tv123,
Six years of a romantic relationship is a LONG time to make memories. I'm so sorry for your loss.
I think the healing you describe sounds on par with normal. It's good that you have moved past wanting her back. She will pop into your head for a long time, and as time passes...and as you gain other interests...it will be less often and less painful.
I've found that this works for me. (It may be psychotic or wrong-headed, but it works for me as I said.)
1. I get a sense of closure, as close to reality as I can while putting a positive spin on it. This is easy when you do the breaking up, because you likely had a good understanding of why you were going to do it. It's much harder when you are the one who is left behind - rejected. Rejection is hideous to everyone, but we all have to face it several times in our lives.
I tell myself my time wasn't wasted because
1. I learned things about myself in relationships that I needed to know or
2. I enjoyed my time with the person or
3. The relationship was practice for the enduring love I'll find later...
You get the idea.
Once I can wrap my head around what happened and why, and I can look at it as generally a positive experience, when I have a memory with a song or someone who looks like him, I'll let that pang of pain have a moment - and then I make myself smile, I visit my positive closure mentally and purposefully. In that way, you aren't a victim of a drive-by heartbreak. You give it a moment, and then you take the wheel. You have turned it into a positive, and that control, for me, made a great deal of difference. I'm not left feeling rejected and sad, but empowered and smiling.
I hope it works for you.