I feel the same way as a 2012 college graduate. Most of my college friends are still unemployed or working in marginal work (temps, office admins, phone support). On top of that, most are buried in student loans (private college) whereas I had parents able to pick up the tab. More than one has turned to webcam porn to make money while I'm charging $$$ as a software contractor.
I post photos on Facebook from Tokyo or Berlin and sometimes wonder if I'm pissing off my friends.
I don't think you should stop posting photos from your trips just because you are 'afraid' you will be pissing off your friends. They can always unfollow you (or whatever FB allows you to do, I'm not big on social networks) if they find it 'offensive'. I just think it is a balancing act between sharing parts of your life, and sharing absolute numbers or boasting.
Anyone that knows me for more than 5 minutes, knows I'm doing well (I live in a nice place, in a very expensive area for example and I don't hide this), but at the same time, I avoid letting (outside of very close friends) people know how well exactly. I never talk about money or salaries or what not. That doesn't mean I won't invite them over for dinner/a swim in the pool just in case I 'piss them off'.
I post photos on Facebook from Tokyo or Berlin and sometimes wonder if I'm pissing off my friends.