One thing that's helped/helping me to detach is when someone said you have to face that your old R is over. It's done. If you two come back together it will be a new R, with building, dating, etc.
I do think about things we did together a lot, but talking a friend of mine who never got back together with her ex she said it's not a problem and she talks about him when she talks to other people all the time. Of course they had good times, they shared experiences and those will never go away. Just because her R ended and never reconciled doesn't make all those trips and things suddenly bad. It made me review how I felt in those instances when I'm reminded of things we did together.
