Wells...without getting all cerebral about this.....I think that what you can chalk your feeling up to is mostly human nature......
The nature of Human Nature is complex, and I don't think that any of us can claim to completely comprehend all of it.
Foe example: In our primitive lizard brain....I believe that there are still rudiments of basic territorial and competitive behaviors/instincts. For someone that we have mated with to be with another can still stir those emotions, to some degree. In more prehistoric times...the interloper would probably have been wounded or killed.....nice, huh?
Learning that one we were once with, is with another, almost,universally, causes us to feel weird for a while. It goes away, after a while, though....
I know I must have said this to you, more than once....(because I say it hundreds of times, here on SR..lol).....That--you are only 7mo. along in the grieving process. It takes longer that this to completely process what has been going on for years.
It takes a longer while to "digest" it all...the kalediscipe of feelings, the various emotions...examining and reexamining your inner environment....until, a new normal is reached and new neurons are laid down......
If you aren't interested in dating...yet, or ever....then I propose that you shouldn't. for Pete's sake...one shouldn't go into that arena when you are apathetic and don't have any appetite for it. (No girl, that I know, wants to meet somebody like that). You have to be ripe and ready for a relationship...or, you will contaminate any blossoming of romance....probably, unconsciously.
I am glad that you are doing well.....I say to give it more time.....Time and Space are such great healers....
Though, it is great that y ou are sharing your thoughts, feelings, and progress.....