I can certainly understand the frustration you are having with obsession. I second what was said above, he fills some kind of purpose for you - explore that.
I have had some persistent limerence, and it is such a frustrating thing. It really does get in the way of living life the way you want to because you can’t, you’re too focused outside. That serves a purpose - for me it is avoidance of things that overwhelm me, an easy high i escape to, and external validation. With fifteen years under your belt it is definitely like an addiction for you, and you are doing the right thing posting and starting to take control of your thoughts and your life. Neurons that fire together wire together. Start making new pathways and connections in your brain.
There is a thread on here, Maia’s survival guide. It is a long post but short and sweet compared to a book, let’s see if I can post link - really recommend reading that.
https://www.survivinginfidelity.com/forums.asp?tid=137622&AP=361&HL=
Also, consider that the strong attraction is triggering something unconscious and likely unhealthy in you - it is not a sign that you need to engage with him. When you get thoughts and fantasies, just say “hello FOO/trauma issues-in-disguise.” Helps me to name it and observe the feeling (I am working on mindfulness and meditating more these days).
No contact. No contact. No contact. Block him. Send a no contact message and block him far and wide across all mediums. Deactivate social media for six months and give yourself some mental breathing room.
Keep exploring your why but know that you don’t have to fully heal and understand to stop your behavior - that deeper understanding can start now and can come together better later.
It is hard but you have to go no contact with him. You may white knuckle it as you resist contact - including checking social media for him. Stick with it. It will get better, it can take a lot of work and time but it does.
There is a YouTube of Dr Joe Beam’s on limerence that I found helpful and easy to digest.
Also, read Not Just Friends by Shirley Glass, someone here Recommended it to me on my own thread a while back and it is a great and eye opening read. You are building a wall between you and your husband by opening up windows that further entwine you with this intruder.
Finally, for a collection of good, quick reads - I HIGHLY recommend checking out the blog Living with Limerence. Dr Limerence’s thing is focusing on living a life with purpose. He has an online “emergency reprogramming course” I haven’t taken but want to. But if not, he has great articles.
Breathe, be patient, focus on what makes you grateful for your husband. Journal. Exercise. Don’t drink much. And avoid the shit out of that guy. He is a loser who wants to take a married woman away from her husband. An Si person I message with told me to consider how he is getting off on that fact quite a bit, he wants to cuckold your husband. What a shitty thing! He may even want to get back at you in kind (FYI, despite being motivated by jealousy it was right of you to tell his wife way back when).
Oh, and tell your husband. I didn’t want to at first either but I did and it was the right thing to do.
[This message edited by Justsomelady at 9:15 PM, September 25th (Wednesday)]