I know you wrote to here a long time ago, but I hope one day you are able to see this message, and everyone else on this thread. I am so grateful for what you said, and everyone else here. I have spent my whole life with this issue and experienced everything you are saying, it has also completely ruined my life and no one understands at all. I am now in my late 20s, and I am scared to laugh and enjoy social situations, even though I am an extremely social person. I now feel socially isolated. I have done it to myself both consciously and subconsciously on purpose. I have become very 'serious' out of fear that I might uncontrollably laugh. But no one understands this at all.
I have, however, somewhat found a psychological solution after obsessively analysing this within myself throughout my life. Although I have yet to properly test this in varied social situations, I can still speculate as to why it happens, how to potentially stop it and I have some examples. It has been 6 years since my last public humiliation from this. Since then, I have socialised on occasion, not a lot, but I have. I am going to explain a couple situations in more detail and my analysis of it in a moment.
Throughout my life I would laugh uncontrollably at hilarious things and find things extremely funny to the point where sometimes I wouldn't be able to stop laughing. It was this psychological 'clinging' onto the laughter or the comedic image that I felt I could have some control over. My mind would keep thinking about the funny thing in a self indulgent kind of way. It was always at that point that I would lose complete control. I can't speak for everyone else's experience, but I would be really interested to know what everyone here thinks of this. Next I will give some examples & a further analysis.
Example 1. I was with my boyfriend (who isn't a very funny person, but can be at times & we can be light hearted and vaguely laugh). I got him high on cannabis for the first time and we both hit the giggles. I had never hit them that hard before on cannabis because I have a natural immunity to anything thats funny now. But this was a very unexpected situation. I started to laugh but I was sitting down so it was ok, I was able to put pressure on that area to stop anything from leaking. But then, he needed me to stand up and help him because he couldnt feel his legs (which was also hilarious). I stood up and as soon as I started laughing I had to cross my legs to prevent anything from coming out. It was extremely funny, so I then had to kneel on the ground to stop it, but psychologically I told myself I had to take control and stop laughing. If I had continued standing up, I probably would have leaked everything, but sitting down saved me (as it has many times before). Luckily, my boyfriend loves me and isnt judgemental so he didnt question me sitting down to stop the pee from coming out, whereas in other social situations people would question it and would find that weird. I found that taking a deep breath in & ignoring the funniness of the situation really saved me from leaking everything. The sad part about this is, I cant enjoy funny things as much or for as long, but this might just be a sacrifice we have to make.
Further analysis: I found that this was a lot easier since I am completely comfotrable with my boyfriend. Upon further reflection, there was no social pressure to conform to the hilarity of the situation. I didn't have to feel bad about becoming serious all of a sudden and worry what the other person would think of that. I am a people pleaser and tend to value conformity over taking control of the situation to my own benefit. So this is something I have to be stronger about and learn to do. To only focus on what is going to benefit me in those kinds of situations and be strong enough to take psychological control over it, even if the other person wants to continue to laugh and find it funny. You can also pretend to laugh (which i did a little towards the end just to be more inclusive and warm about it).
Example 2. I was with my mum and we started unexpectedly laughing about something, and a similar thing happened to the previous situation. I felt comfortable enough around my mum to cross my legs and take more control of it. So I think I just need to practice doing this more. Unexpectedly funny things are the worst thing for this. If I'm watching a comedian on the other hand, I can choose what and when I find funny. So my thoughts are, something can be unexpectedly funny, but the moment it is, to train my brain to take control of it in that moment and to not allow myself to indulge in the comedy of it UNLESS I am sitting down. Sitting down seems to be the only way I can laugh, but even at that, I have to be careful for how long I laugh for and always take control of it.
I have read in some comments here that confirms this is a psychological issue. And that say Ritalin works. I wish I knew about this cure throughout my childhood. It would have completely changed my life for the better and I would have been able to develop close friendships with people. But sadly, I had no help. It ruined my life completely. Now that I know about ritalin, I am going to use this for when I'm next in a social situation that might induce a lot of laughter. Even just knowing about that makes me feel a lot better about putting myself in those kinds of social situations without having to worry about being so serious and uptight around people. So thank you all for that. But, I still want to work out a way to do it without that. If it is psychological, there must be a way to train certain parts of the brain naturally (an area that big pharma don't seem to spend any effort or time on at all). I don't want to be confined to a life of taking prescription medication. I try to be as natural and healthy as possible. But I will keep trying my own experiments and keep everyone updated on this forum. I hope you are all still out there listening.