However, getting jobs is more than that. Or, rather, getting and keeping a job is more than that, and that's where I worry I'm lacking sometimes. While I wouldn't flat-out say I don't work well with others, my patience has gradually gotten worse and worse over the years. At my last company, I think I likely developed a reputation as someone who preferred to isolate himself, someone who should be exempt from any established company processes (stuff I always felt hamstrung me), someone who prefers to just be given a thorny problem and then left alone, unaccountable, until it's done.
Certainly what I do (and how I prefer to work) can have value, but it has less and less value as a company grows and relies more on predictability and consistency to get work done.
Over the past year and half or so, a lot of the longer-tenured folks (including me) left the company I was working at. I've kept track of where a lot of my former colleagues have gone, including those who were (and still are) in management positions, and sometimes I question how many of those people would really want to hire me at their new company. While I do good work, I could see them thinking that I can be hard to work with at times, or that I might not mesh well with the rest of their team.
It's possible I'm coming down too hard on myself, and it's not that bad. But it's something to consider: having technical skills is great, but it's not the whole picture when it comes to being easily employable.
As to the root of your issue, the stress and anxiety when things are bad, I think the best thing to do is remove external control over your destiny. Live well within your means, and save as much money as you can. If you have enough savings so that being unemployed for a year or more isn't going to put a strain on your finances or require you to change your lifestyle, then that should reduce your anxiety level quite a bit.