To dream that you are masturbating implies that you have hidden fantasies and requirements regarding sex. It suggests that you should satisfy some inner personal needs. Perhaps you should try harder to strengthen the bond between you and your significant other.
To see others masturbating indicates that you are nervous about expressing your inner feelings and emotions. You feel restricted. It's possible that some aspect of your life isn't gratifying enough. This dream doesn't always have a sexual meaning, but it may be indicative of some issue or association in your life.