Um, no. I mean on the guarded thing- I do actually know where a good bit of that comes from. At least where a good bit of it likely comes from.

I suppose I may have given the impression I have absolutely no idea, which isn't the case.
I mean, I've experienced the average, every day "betrayals" and hurts that everyone experiences through life- no biggie.

But also I've had some other stuff happen- maybe by themselves it might not have made an impact. Undetermined.

One incident involved a doctor blatantly ignoring some important symptoms to the point where it likely caused some harm because I didn't get treatment for a long time, and on top of that he wrote some blatant false statements in my medical record- not just misjudgements or inaccurate observations... lies. You all reading this can make your own determination on whether or not that is crazy talk, obviously. I will say it is a fact and something I experienced and may yet have some negative repurcussions, but of course you all are strangers and are free to make up your own minds about whatever it is I say.

Another is that, while working in a fairly public position doing internet crap, some people decided they didn't like me and very very publicly and very very brutally decided to basically drag my name and character through the proverbial mud.
And the swamp.
And like...tar and feather it, set it on fire, put it in a blender, turn it into sludge and feed it to the hogs. [I don't know, add some other nonsense as well]

I was accused of various things, repeatedly and very publicly, but I will just say that intent to harm physically harm someone was one of them, and the other party posted as much personal information they had on me any where they could.
No big deal you say?
Well, at the time i was kinda trying to keep personal info off teh intarnets because I had a very serious case of "stalkeritis", and said stalker lived about 20 miles from me, and at the time was still writing about me publicly. Just didn't know where I lived.
This party who shared my information was well aware of that.

So reasons for being guarded?
Do I have them?
YOU BETCHA

Can I discuss with my really good friends of many years that I feel terribly isolated even when with them?

...no. No I don't believe I can.