You're not alone! Everybody gets frustrated when studying for the GMAT - it's a tough test!
I'm not quite sure whether you're
asking how hard it is to score 500 or just want to
tell us that you're finding it hard to get to that level. If you're asking, it isn't really a matter of "easy" or "hard." You have a certain starting level, whatever that is, and you have to do some amount of work to get to the next level - the more you want to improve, the harder it is. Someone starting at a 400 is going to have more work to do than someone starting at 450.
If you'd like to get specific advice according to your strengths and weaknesses, you can use the below article to analyze your most recent MGMAT CAT:
http://www.manhattangmat.com/blog/index ... ice-tests/Then, come back here and tell us what you discovered. Note: share your analysis with us - what you think the data means - and not just the data itself. The ability to analyze your own work and figure out what to do with that information is absolutely crucial to your ability to improve.