Does not going to graduate school make me a failure?

Deciding on going for a Masters degree should be based on if your job/career would benefit from you having a higher degree. It has nothing to do with being considered a failure.

Talk to your college adviser. See if you can retake any of your classes right now at your university. 

Do research on graduate schools. See which ones have a higher acceptance rate. 

Retaking those courses at a community college will not look good to graduate schools.  Community college courses are generally viewed as less rigorous (even though that's often not the case) and it will look like you're just trying an easy way out.  See if your university will allow you to retake those courses; even if you can't replace your grade in them, doing better in them will look good on your transcript.  

Don't discard the possibility of graduate school with some Cs.  You may not get into a top graduate school but you may find yourself a good candidate at some programs.  

Finally, you are not a failure if you don't attend graduate school.  MANY people make a good life for themselves without attending graduate school.  But if you think graduate school is no longer in your future you should start talking to advisors and/or career counselors about your options after you graduate.