Thanks ValNTine, despite our problems I really do feel blessed to be with my wife and to still be in love after ~15 years. I've always appreciated that I could be frank with my wife (and she with me).
Sorry for the longevity of this post, but answering all your questions (hopefully I got them all) took a while.
I want sex far more often than my wife. If I could wave a magic wand, my wife and I would ML 1-3x a day. I strongly suspect my libido is a lot higher than most guys my age (almost 40), but I've been that way since a teenager. I'm definitely content with having sex 2-4x a week, and these days we either achieve that or come close.
Our biggest problems these days come from differences in desire, passion, and stamina. We also have issues, as you already know, with pain during sex for my wife.
The pain is mostly caused by clitoral overstimulation during sex (after she is done having orgasms). It's that overstimulation that typically marks the swift end of intercourse. Typically when this occurs I've not climaxed and she'll stay with me and try to help me. This is the only time these days she masturbates, because she can often times draw another orgasm from pressure (w/o clitoral stimulation). She primarily does this to keep herself in the moment which helps me (and frankly I enjoy watching her be pleased). We've started using a silicone based lubricant which seems to help some with this pain (more on that later).
Another type of pain she gets is a general rawness (not clitoral) that can start during the middle of sex or appear after sex. This can last anywhere from an hour to a day or more. When raw, even penetration can be painful to the point where it's basically impossible. I can feel when she is raw during penetration, it feels to me like she's exceptionally warm at the vaginal opening and sometimes further in the vagina itself. This typically ends sex before it starts or during sex if it flares up during. At times it seems that lubrication helps, but it's far from being truly preventative.
She can feel like to both of us that she's properly lubricated and yet the pain can flare up. Sometimes it can start before she's had an orgasm but typically then she endures it because she wants to climax and the pleasure outweighs the pain. I don't know when the pain flares up until after sex is complete or if she tells me. If it flares up before she climaxes she typically doesn't say a thing.
I believe the longest we've had intercourse is perhaps 15-20 minutes. Typically once she's achieved her 1-3 orgasms, even if the pain isn't there she kind of turns into what I describe to her as an anatomically correct rag doll. That is she's not in the moment at all, her mind immediately goes anywhere and everywhere despite her best efforts to try and stay in the moment.
We typically use two positions (missionary and her on top... guess it's called asian cowgirl?), which is a mild disappointment for me, but frankly if we used only two the rest of our lives and our other issues were gone I'd be delighted! Her legs pretty much need to stay on the bed (aligned with her body). When we raise her legs too much during sex she gets very uncomfortable, not because of flexibility but because she gets the feeling that her organs are being pushed around. We get the same results whenever we try an position from behind (doggy) or on the side.
We saw a ST for the first time last week, and that went well. Mostly we just went over background, but she did leave us with one good bit of advice which was to try using silicone based lubrication. We've always used water-soluble before which we found wasn't worth the effort (in fact at times it seemed to make things worse for us). Time will tell if the silicone lubricant is something that will continue to work well for us only time will tell, but we are really happy with how things have improved so far. We plan to continue going to see the ST once a week in the immediate future. We also hope to touch on the issue of her lack of passion, as it's something I'd love to feel from her (more than perhaps 1-2 times in our 15 years of marriage).
We've never brought sex toys into the bedroom. Not because we are opposed to them per se, just have zero experience with them. LOL we had to look up what a fleshlight was, and once we did we had a lot of fun talking about it until she fell asleep. We have a similar sense of humor, so it was actually a really great time tonight just laughing... to the point where at times we were worried we'd wake up the kids. Though that's nothing new, we joke around and laugh a LOT.
We are willing to try anything like that.
Typically during foreplay she'll give me a BJ, followed by me giving her oral sex (she's not a big fan of 69) while I keep myself excited. While I've given her an orgasm a few times with oral sex we tend to not let it get that far because it's overall counterproductive for us. She does enjoy it though, and it makes a huge difference in her being ready for penetration (we used to have a lot more problems with penetration prior to us trying it and making it a regular thing).
I've only had one other sexual partner in my life, a college girl friend I dated for 2-3 years (it ended about 2 years before I met my wife). We were sexually active through most of that time, and I've always taken a while to be pleased. There are times when I'll finish quickly (1-5 minutes), but typically that's rare. Also rare are times when I've tried for 20-60 minutes w/o success and gave up trying to climax. These days I've found if I don't climax in 30 minutes or so after sex has started it's just not likely to happen at all. This only tends to happen when my wife is finished and her not being in the moment makes it hard for me to finish.
Something I've not shared here before, only because I wanted to make sure my wife was OK with me sharing (even anonymously) was that she had some sexual abuse from ages ~6-12. No penetration, but she had her vaginal area touched infrequently by a family member. This caused her to get an early interest in masturbation, which was quickly snuffed out by her mother. We aren't sure if that has any bearing on her sex life with me now, because she has no qualms with being touched. That's something we are going to go over with the ST in the weeks to come.