It's easy to be hijacked by other people and live life on their terms - we are quite competitive, judgemental people after all. So when we see our friends in new cars with their new houses and interesting careers, it's easy to be sucked into their frame of reference, i.e. It's good to have all these things. This is even more compelling when it backed up by the consensus view of society.
However, do not despair! These things only have meaning if you believe in them. If, like me, you have been forced down a different path then these things are meaningless and inconsequential. From where I've been, seeing my children grow up and having a pleasant day are far more compelling achievements.
You might not see this because the way you see the world has been shaped a certain way. If you can, strip things back to what is important and live life through your own frame of reference. Avoid the other way, and start to enjoy what has real meaning to you.