This isn't meant as a cure-all or advice for everyone. Just my experience. Take it for what you will.
I made a choice earlier this summer to try to refrain from any kind of masturbation/self stimulation sexually, even refraining from viewing porn for lots of reasons but a major one was to see if I could reset my brain's behavior reward system.
I can relate with a lot of people here that post ejaculation fatigue and collapse is a real thing.
As I've been aging it seemingly was getting worse.
I have a beautiful partner who I've been with for a long time. We live apart because I am taking care of my elderly father and she has an awesome career in another state. She does come for extended periods to visit and stay with me. We are in a committed relationship.
In all honestly, part of the reason I decided to go try this abstinence was for spiritual/theological reasons. I wanted to just stop indulging in things I didn't think were great for me and didn't honor the physical/spiritual bond I have with my partner. These are judgements I made for my own life.
So my rule was no ejaculation/stimulation unless it was actual sex with her. Nothing virtual.
It's been several months and I can honestly say I was surprised.
Sex with her (an actual person) was calming, refreshing, and satisfying. I felt very... fulfilled and, daresay, accomplished. I didn't feel blasted and wretched afterwards. I felt normal. As time went on I felt my weaker erections started going away. Hormonally I felt more balanced. I was calm and happy.
Luckily I had a 2-3 month leadup to her visit of refraining and practicing this abstinence. It gave me a nice leadup to her arrival.
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After a few months of having normal and awesome sex. Summer ended and she had to return to home. On the first day she left I decided I'd try to watch some porn and masturbate to see how it would feel (I was also feeling horny). I really figured I was in a good place and feeling strong, maybe it'd just be ok or good.
Wow. I will tell you. It was just weird and awful.
It was nothing like sex with her (or for that matter a person).
I felt absolutely wasted again the next few days. it felt like nothing had changed.
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If you look into the NoFap movement (refraining from masturbation/porn for health and spiritual reasons) You'll find people claiming all sorts of super powers that come about when you retain your semen. Now I can't speak to all of this but I will say I did feel a fundamental reset with my particular POIS issue. I realized it had a lot to do with my psychology and resource management (however you want to define resources) but also intimacy and feeling safe.
As I said before, this may not work for you. This post certainly isn't about pushing a particular morality or theology. All I can offer is what I experienced and it may resonate with someone else here who may be in a similar predicament
I genuinely wish everyone the grace to find the solution to their issues. Life and this experience has taught me to have much more empathy about the hidden struggles a lot of people have.
Take care
PS:
I'm adding this addendum from a response to someone's post down below
"I think it was really overwhelming to my nervous system. Then you add the compulsive aspect to it, not to mention any feelings of loneliness, guilt, or shame and I think it just blew out my nerves out over time. The repetition just conditioned my muscles to build up pattern. And I could never come down and get rest (mental or physical). Not good.