I will advice you, or more correctly, him, to develop the ability to have orgasm without ejaculating. This maybe sounds a bit advanced and impossibly to many, but at least this is the way I am making my sex activities last as long as I want to. When I was inexperienced I also came very quickly. But then I started to stop the thrusting, when I was near orgasm. So I stopped, and pulled the penis out and waited for some 5-15 seconds, then continued. The timing needs to be very correct, and he needs to really feel how close he is. The goal is to stop just at the moment such that when he pulls out the penis, it will feel like he is just about to ejaculate, and the penis will start to pulse 2-3 times, just as when ejaculating, and he will feel it as a half-way orgasm, but he is able to NOT ejaculate. The timing here takes some practice to manage. Sometimes he will be too late, so he comes, and sometimes too early, so the orgasm will return quickly. I have not researched much about how this works technically, but the mechanism that makes the penis flaccid is connected with the ejaculation, not with the orgasm. Hence if you can have an orgasm, without ejaculating, you can continue the sex act. An orgasm will reduce sensation buildup in the penis, back to a low level, but it will not make the penis flaccid, if avoiding a complete/full ejaculation. He must understand that this is really like balancing on the edge, he must be so close that often it may come a few drops of cum out, but that's ok. He must definitely experience the penis pulsing, like during normal ejaculating, but that he still stopped soon enough to hold it back. It's like you look at your penis and it feels like you are ejaculating, but then you see that you don't. So if you practice this, and when he fails have fun and laugh about it, and try again, I'm sure he will learn it. Sometimes you need to do this "climax-edging" 2-3 times, because you didn't really reach the correct spot, and then you can continue again for some minutes more. After each time he stops, if hitting the correct spot(time), he will be able to continue for longer than the previous section. What is good about this is that it learns him control over his ejaculation. And with practice he will also last longer. But the good thing here is that the goal is not really to avoid or postpone the PE, cause that can be very difficult or impossible I don't know. Instead you just make yourself able to repeat the process over and over during the same sex act. So the only draw-back is a few short pauses, which is not really negative even, can be exciting too. And the PE will improve, but as a secondary effect over time, and you don't really have to think or worry about that part at all.
So this is really to get closer with his penis. Another thing you should try, which is kind of unrelated, but a nice thing to add into your sexlife is a way to give him an awesome handjob, with a long-lasting orgasm/ejaculation. Best if he is sitting, and you are on knees. You can start with a normal blowjob, or handjob with oil for example, then when he gets not too far away from orgasm, you stop touching the penis head, and the upper 1/3 of the penis. Keep your hand at the base of the penis, and do very short jerks, a bit slow, while squeezing it firmly (with your full hand, not just a couple of fingers). This reduces the pleasure, but it brings out the orgasm from a much deeper level. It builds up quite slowly, from the inside, and he can really feel like he is coming, but he can have this feeling for quite long, maybe 10, 20 or 30 seconds, which is fantastic. And when he comes, you shall just continue the same motion in same speed, as you will see he will ejaculate for about 10 seconds perhaps, and shoot really far. So this is mostly about you, trying to sense when he is getting ready to come, and then slowing down. Actually, there is nothing wrong with doing the complete act in the slow way, with no touch of the penis head. It will take longer, but if you are able to reach goal in 10-15min, then it's probably even the best way to do it. You can also pull very lightly in his balls with the other hand, but not necessary for this to work. But there is ONE thing that you MUST demand from him to make this work, and that is to NOT tighten his leg/seat muscles, but relax completely. It's a natural reflex, when getting close to orgasm, to tighten the seat muscles, but doing this makes the orgasm come quicker, and it will not be so powerful. So pay attention to this, that he doesn't tighten his butt, but sits on soft relaxed muscles. Actually, this is really interesting, cause it also connects to the females. The way to make a girl have a "squirt", is for her to relax the muscles during the orgasm, and if she feels that she is going to pee, then not to hold back, not to tighten, but just let it go.. Cause that is squirting, not peeing. So for both sexes, relaxing during orgasm makes it stronger. These things are not so easy to practice during intercourse, but works best for handjob/fingering. But that's a great part of sex, specially when practicing these methods.
Ok, at least that is how things work for me. People may of course respond a bit differently I don't know, but I think it's mostly just to "figure it out", I think we are not that different in the end, we just start from different conditions. so there you have one method for dealing with PE, and one very enjoable thing for him, that should throw a new interest into your sexlife. So I suggest you also let him read this description, and please ask if you have any questions about it.
I will not discourage a sex therapist, I never tried one, but I really don't think it will help. Only way to make this happen is for him to get closer connected with his orgasm mechanism, which I think the things I describe is the best way. Don't think about the mental part, cure it physically, with such practice, and the mind will follow. The great part is that you can have as much fun, desire and experimenting as you want while doing this, as long as he does this "edging" at least a few times before he ejaculates completely. Get on with doggy-style and everything you want. It doesn't matter if he reaches the edge sooner with doggy-style as long as he tries to edge it. That will probably just make him hold it longer in a less exciting position. Like the sprinters.. they practice 150m sprints to be able to have stamina for the 100m..
And have sex as often as you can, and at different location. I really advice you to step up your activities, while including these methods, instead of trying to "calm it down".
..Just as a side note; this is not Erectile Dysfunction, as he has no problem getting erection.
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