Formerly worked for an ESA subcontractor, I was paid about the same as during my Ph.D., so not particularly great. Mostly did it out of interest and because it looked good on my resume. Switched industries and my salary increased by about 30% overnight. About a year later I was already at 50% more than when I worked there, and had a far better benefits package. So that salary seems quite wrong to me.

But as to the work itself, fun job contents, technically very challenging, but a horrible work environment due to agency politics and questionable management policies at many of the defence contractors out there. For example, as an engineer you don't particularly enjoy being entangled in drawn out politically-driven discussions, but that's the position you end up in when you make choices about hardware procurement in those projects. And then you got to deal with folks asking the most ridiculous questions imaginable for hours on end to try to make you sway, and you can't lose your temper at any point during said question rounds, and after months of that you can finally use the technically correct solution. It's bloody atrocious to deal with and the two years I spent in that industry noticeably aged me, it makes dealing with academics who have a rod stuck up their arse look like a relaxing day on the beach by comparison.

And then we haven't gotten into the sunken cost fallacies inherent in these projects, etc.

>and yes that is the plan, limiting my time around them and basically avoiding them till they get the hint.

They won't get the hint, all it will do is make you seem more absent, slowly increasing the distance between you two, cutting them off slowly or frustrating them to the point where they cut you off. This method never works and might achieve something you don't want.

Before you do anything in particular, ask yourself: Does your friend even have anyone else to talk to about the issue at hand? Why is this so important to them? If you want someone to back off in terms of complaining it's often a good idea to look at the reason why they're complaining to you about something or someone.

If I may be blunt here for a minute: that's kind of a douchebag move on their part, ghosting like that means they were probably never a real friend or have a horrible personality. You might not actually want that person in your life.