While it's true that finding things to appreciate and feel grateful for can elevate your mood, (as the guided meditation here might demonstrate), be careful that you're not using it as a way to by-pass, get away from, or resist negative feelings.
Judging yourself for having negative feelings, comparing yourself to others who "are worse off," and forcing yourself to feel grateful, will ultimately make things worse. Like positive thinking, it can simply add to the tension between the judging-you and the part of you who longs to be heard and needs your compassion.
Neither the judging-you or the hurting part of you is who you are. Think of them more like characters in your inner drama or play, who were created in response to stressors in your early environment, and who adopted the coping behaviors of others in your childhood "play." Who you are is the one who observes, who watches the play without judgement. Who you are is the space on which the play unfolds.
This you is big enough and vast enough to hold it all and the more you practice making a compassionate space for all of the parts of you to show up and have their say, the more you will experience and know yourself as the truth of who you are.