When the feeling emerges, just let it out!
Yes, there may be some circumstances where you may need to wait a bit, but be sure to let it out. If you feel a surge of sadness come over you, cry it out.
If you need to talk about your feelings, confide in someone you trust.
Don’t tell yourself to “look on the bright side.” Don’t tell yourself to focus on all the positive things.
Just accept the feeling that you are experiencing and allow yourself to release it.
You’ll notice that you feel better in doing so.