What's the best way to stop fixating on sadness and try to focus on the positive when your mind is clouded by depression?

I personally think that if one can shift their mindset to focus on what they are thankful for, then that can help change their mood and fixation. However, I do know that major depressive disorder (major depression), along with other depressive disorders are very serious (but manageable with the right tools) mental illnesses and not just simply "sadness" or a fixation on it. In that case, if one has the energy to, they can reach out to a friend or a listener here with whom they can talk to about what they are experiencing. Another option is to set something up where a friend or two can reach out and check in as well.