All-time, the evening the woman I lived with in Paris for nearly a decade decided she wanted to be with me. After a couple of fairly iffy dates, we went to see the film Barry Lyndon; I’m not sure what it was, but she practically jumped my bones in the Metro going home. Thanks, Stanley Kubrick!
Finding I’d made it to the point where I could buy a house wasn’t bad.
In recent years? Scoring a ride in a B-17, on a gorgeous June day over Galveston Bay.
I thought about many things I could say here. There was my college graduation, which almost never happened because of various lows, but now because of those lows I don’t look fondly back on it. There was meeting my first wife, which was a beautiful story which I’ll someday tell but it’s too long for this sentence, but then she cheated on me through most of our marriage and I don’t like remembering anything about her. There was marrying my second wife, but then I remember how my parents didn’t bother to come and I don’t like remembering that. There was getting promoted at my last job despite the extended (and quasi-legal) efforts of my then boss, but not surprisingly I had a nervous breakdown soon afterwards and so that wasn’t all good either. It seems like every high I have had has been tinged by problems or mental breakdowns, and my good memories are jaded by surrounded by the bad ones which have bookended them.
So as long as I’m going to have to pick a gem from a mountain of fragmented rock, I might as well just go all out and pick one from my awful experiment in polyamory. Almost every day in that ill-fated relationship was horrible, but that first night…
It’s hard to say, I’ve been very fortunate to have a pretty great life, by anyone’s standards. I sort of think of my life in sections, so I’ll give you four.
Childhood:
When I was about 10, I started riding my neighbor’s horse (bona fide wild mustang, have NO idea what my parents were thinking allowing this.) After some months, my parents declared to me, without my even asking, that they were getting me my own horse. (Horses, plural, as it turned out.) I’ll never forget that moment, when my mom told me. And with some breaks for other stuff, horses have featured in my life ever since, to my great happiness.
High School:
Found out I made National Merit Finalist, which meant I really didn’t have to worry about paying for college. I still feel like I didn’t deserve it, but it was a highlight, for sure.
In between:
I backpacked around Western Europe, solo, for 2 months in between high school and college. The whole trip was just so perfect, it really changed me. It’s an experience I wouldn’t trade for anything.
Adult:
Buying our first house (my husband and I), which was a fixer-upper and an enormous bargain, and we had so much fun finishing it and made so much money on it, that we never stopped with the investment real estate, and it’s been fantastic for us. But getting that first one was a blast. Actually, I love buying houses, every one is fun.
So yeah, great life. Lucky me. 
In the past month, it’s been the big hug I gave my daughter when she got her master’s degree in social work. That’s a big accomplishment for anyone, but this past year for her had lots of ups and downs. We were able to get her through the downs, scared that she’d drop out of the program with just six weeks until she was finished. So, when she finally graduated it was a huge highlight and relief in my life, and hers as well.
It’s tremendously difficult for me to think of a singular high point. I’ve never had a time in my life where I thought “this is so much better than any other experience I’ve ever had.” My life has tons of high points. And a shitload of low points, too. Right now, it’s going to be the last high point of my life: the birth of my daughter a few weeks ago.
Well, either that, or our lives just suck. Whether that would be true of just Dopers or the population in general, I don’t know.
Maybe not the personal high, but a personal high for me is when I met Haley Osment. But not just because of that. It’s because it might not have happened, certainly would have been more difficult, without my husband’s assistance. I didn’t have a car, so I rode to work with him and hung out on the Sony lot all day, then we drove over to Fox, where he’s also worked so the gate guard knew us. My husband was as happy for me as I was for myself, and that means a lot to me. In fact, I just told him so.
And beyond that, it’s the only time I met a celebrity that I really had my heart set on meeting. I’ve met plenty of celebrities, but rarely anyone who I was already a fan of. So I was lucky enough to 1. live in L.A. 2. have a husband who wanted to help make this happen and 3. be experienced enough at meeting OMG FAMOUS PERSON that I was able to be cool about it. And that added up to one pretty great evening.
It happened last week, and I started a thread about it. I got to experience a catapult launch from an aircraft carrier courtesy of the US Navy.
So far, nothing else has come close. 
My personal best was when I found out I got a full scholarship to the local college. There was literally no way for me to go to college otherwise - my family was poor, had no assets, etc. so no one would have loaned us money. Even a Pell Grant wouldn’t have covered everything.
I went from “maybe, maybe I could go to college” to “wow, I get to go!” in like 10 minutes. 
And then my best friend at the time crapped all over my accomplishment by saying, “well, it’s not like you got a scholarship to a PRIVATE college.”
Yeah, but I ended up with ZERO student loan debt, bitch!
She’s not my best friend anymore, thank God.
After being stabbed next to my heart I picked up my attacker by the neck with one hand and pulled the knife out with the other and lived to have her ass thrown in jail. I felt like I was touched by God.
Then there was*** that*** girl in college who was the best of the best. Same feeling only different.
I applied to go to Duke University and was accepted. Didn’t go, for financial reasons. Just as well – flunked out of a state school.
I was targeted by a terrorist bombing, I guess that’s sort of a high. It was a Molotov cocktail that was made wrong, and just lay on the floor and burned itself out.
As Mark Twain said, about being tarred and feathered, “If it weren’t for the honor of the thing, I wouldn’t have enjoyed it at all.”
-As an NCO in the Army, training up and leading an entire team of new recruits through a skills competition and handily beating the rest of the battalion, including my former team leader and his team of vets. That guy was such a blowhard, and we kicked his ass. I am so proud of beating that jackass, I can’t begin to explain it.
-My wife telling me I did a great job helping her through the birth of our son.