You are not selfish. He is stirring up insecurities that he has enforced in your marriage. It's normal to feel at a loss or to have to grieve the good parts of the relationship and when you do this it's hard to think of the bad.
While I don't know your relationship or the abuse, I feel like I should mention triangulation. It's talked about alot in narcissistic abuse. Triangulation is an abuse tactic when bringing a third party into the relationship. While I understand that the relationship is technically over, I just wanted you to know that the feeling not good enough, the "why did he not do that with me?", the jealousy of moving on so quickly (if he is), and the general confusion felt can actually be an abuse tactic and manipulation in itself (caused by triangulation).
It keeps you hooked to the abuser and can also work to create jealousy, insecurities and a feeling of loss that can act as a way of drawing you back into the relationship.

Many narc abusers use triangulation. Some will actually use forms of social media to hurt their former partners by posting loving images of their new partners. It may have actually crossed his mind that you could be tracking him. I don't know.

You have done so well to leave the relationship, don't let him sway you back into the cycle because of the insecurities that he has cemented in you. Be strong, do the things that he has stopped you from doing for so long because he made you feel unimportant. You are, and you have the control now to change the way you see yourself because you can't change him.

I have found this YouTube channel (Inner integration) really helpful learning about abuse. While the link i'm about to send may not be the most relevant to your situation, it may though, there are a lot of videos based off questions that abuse victims have including how the abuser can move on so quickly and (what I found relevant to me as I thought I was nuts :) ) why you stalk your ex narc
https://youtu.be/Z-Vv0qpK_mE

Thank you for not being judgmental about me tracking him. I know I shouldn't and I know I wouldn't want him to do it to me. But it just hurts so much and I keep thinking the truth will bring me closure. He admitted it this morning. It's a woman he's worked with for years. She's older but very pretty and in good shape so she's smaller than me but strangely... even though it hurts... I feel a little better. thank you all for your support and I will check out the YouTube video after work tonight! I've found education helps the most

But please keep me in your prayers today as I struggle to deal with these super confusing emotions. For a few minutes I can breathe and then for a few minutes I'm smothering!

Nothing about what you've
done or felt is abnormal.

The biology of the brain
has a lot to do with why
we still feel bonded
under circumstances
that suggest we should
be doing a happy dance
to have escaped and now
have the predator focused
elsewhere. (Pity the poor
next victim!!!!!)

If you haven't already,
please consider two
things.

One is to find and work
with a qualified therapist
whose specialty is
recovery from abuse.

The second is to give
Ilene's Clarifying Index
Card exercise a try. I
developed it for myself
when I was breaking
away from a fifteen-year
abusive marriage. It
helped me and has
since been of value
to others. I'll bump
it for you.

Finally, now is the
time to put all your
focus and energy
on YOUR SELF!!!!!!!!!!!!!!!!!!!!!!!!!

Sending you hugs
and wishes for
healing and
better days
ahead.

The drive for closure from the confusion and pain can lead people to do things out of their ordinary, that that would never see themselves doing for sure. There is no judgment, you're seeing the truth and getting back in touch with your intuition.
The back and forth love/pain feelings of confusion is the cognitive dissonance that is experienced from abuse. It takes time to overcome, just don't let the good times blind you from the abuse.
Are you seeing/talking to a psychologist? As far as closure goes, talking to a psychologist will help. You will never answer the "whys?" about him. Instead talk it out, let yourself go through the process, and in doing so it's about seeing the abuse and the abuser for what it is, and understanding yourself and what he manipulated in you. When you stay strong, and distance yourself from him (no contact is recommended), and work on healing, the why's become less important. Stay strong.

I am working with a therapist. I'm doing cognitive behavioral therapy and EMDR for my PTSD. I seen her Friday and everything was fine haha can't wait to discuss this with her when I see her again. Hopefully by then I'll have dealt with it. The last few sessions she's told me I'm "healthy adulting" haha but I can definitely feel andifference in my strength and mindset. Instead of an every day battle it's become a couple times a week battle. I'm working toward the day when the battle is finished!

Good luck.

I have too have hopes for when i do EMDR.
I have been on her waiting list. My therapist Says
she is good so i will wait. I have trauma Much of it
the same as you, i need to face my reality and its
Been Very hard no matter what i have done.

I am finally Detached and unbonded from my ex
that Has helped me a lot. Now i am focusing on healing
The abused me of the last 12 years we were together.
The first 18 years seemed fairly normal with some issues.

I seem to have a hard time with the index cards or the
journaling I just tear them up after i reread them. Writing
them out Once is more than Enough, rereading is too much
on me and my emotional MH, HUGS

I can't bring myself to write out the index cards. I've only had a few EMDR sessions and it made a huge difference but EMDR required me to write down any significant memory between birth and now... when I got to the part about my ex... I couldn't do it. I can't journal about it and I can't write about it. It makes me physically sick and my brain shuts down. She says we will get to that and we are working on it but there's not much further I can go with EMDR until I'm ready to face what happened but I just can't. I can speak of it but to write it down.... somehow that makes it more real and I just can't. I hope things get better for you and I'm looking forward to how EMDR works for you! I didn't notice anything the first session but the second and third made a difference! Hugs!!

Lynn, let yourself grieve your losses you are pretty
New to this. I will be divorced 2 years next month
And No contact for almost that long. I still go to
Alanon And attended divorce care multiple times
and have a great Drug, alcohol and abuse therapist
who is also a 12 stepper.

Divorce care is great and helped almost as much
As alanon. I found my lost soul and learned To trust
God again. I had rage when i started and ended up
In forgiveness. I still embrace my healthy anger that
Keeps me safe.

Where you are at i would not push yourself on the
Abuse issue until you are ready. I have been doing
this Work since 2012 and just getting in there deeper
Right now. I had a lot recovery under my belt and I
Am finally detached.

There such a thing as retraumatizing yourself just
Be careful. Trauma is funny and most good therapist
Won't push you until you are ready. My therapist and i
Have talked openly about Abuse right from the start.
HUGS

Thank you. I have been feeling so odd about not being able to confront that part of the relationship so it's good to know that it's common to not be able to until later. It feels like I make huge strides and then one day I just crumple and almost go back. This starts the whole process over again. But I'm staying strong and continuing to move forward! I'm so grateful for the support of this group!

Alanon and CODA meetings helped me a lot too
with all this stuff. I come from narcissism, dysfunction
and Alcoholism so take your pick. I married a Dry
alcoholic and i am a recovering codependent and
Doormat:)

I think with me its the cognitive dissonance is
Giving me a hard time and my brain is not ready
Yet to go there its too hard. I have been on edge
Ever since i started i can feel my uneasiness. HUGS