Thanks, everyone, for your helpful replies. I'm new to this and just trying to find my way, so having all this experience to draw on is very helpful. I'm learning right now and a long way from bringing this up with my wife, if indeed I ever decide to do so.
AT THIS TIME. At this time that is your belief. Well... you could examine this belief.
Why not? Why couldn't you meet someone and make a deep emotional connection, just as deep as the one you have with wife? If it did start to happen, what would you do, dump the person immediately?
Why would you want it, or not want it?
My belief stems from the fact that we have been together for 35 years, and our bond and emotional connection, which started strong, has only grown from there. I think if I were to develop a relationship with someone else, then in 35 years time my primary relationship would have had 70 years of development and still be ahead, in that sense. Now, I'm not stupid. I know that these things don't necessarily develop in a straight line, and throwing in sex as well could accelerate the development of feelings for this putative other person.
Why would I want it to work out that way? Well, for 35 years, my wife has been the most important person in my life (with the exception of our son), and I've been the most important person in hers, and I don't want that to change, for her sake or my own.
I know there are no guarantees. We cannot necessarily control our feelings, never mind those of the other potential partner. But really, what in future life is guaranteed, anyway? We have to make the best decisions we can and live with the consequences of them.
If what you want is more sex... well... what kind? Like hiring a professional? Developing a FWB? Seeking a regular GF? Something else?
Once, years ago, when I was working away a lot, I decided I would get an escort and pay for sex. I had convinced myself that due to the transactional nature of the encounter it wouldn't be cheating. I went as far as calling one and leaving a message on her voicemail. However, by the time she called back, I had realised I was simply trying to justify myself and it wasn't acceptable. I never answered or returned her call. (Perhaps that was rude and cowardly, and I should have spoken to her and explained my change of heart.)
I think casual sex would possibly be thrilling and exciting. (And who doesn't like those? So I'm certainly not ruling it out.) But I think, ultimately, it would be unfulfilling for me. So yes, I do want to have more of a connection with someone than just sex, but I don't want to replace my wife and I don't want her to feel replaced. I think I would be capable of making an emotional connection with someone without it diminishing my connection with my wife. At least I hope so.
Is your definition of "sharing sex" very narrow, like "only penetrative sex counts as sex?" Would you and wife benefit from sex ed or sex classes? Learning other ways to share sensuality/sex?
My definition of sex is actually very wide. My wife and I have had very little sex. She experiences vaginismus and we have never achieved penetrative sex. Since I hadn't had sex before marrying her, and haven't had sex outside of our marriage since, I was always of the belief that, over time, that issue would either sort itself out, as she became more comfortable and relaxed around me, or if, necessary we would get help to sort it out. I didn't know, at the time, that the issue wouldn't be what kind of sex we were having, but the fact that we were not having any kind.
One of the things I'd be looking for is not most people's definition of sex at all. I'd love to just lie in bed holding someone and being held, ideally both naked to feel the skin-on-skin contact, not doing much else. Maybe we'd be talking, or maybe not even that, just being together.