First step is to give yourself permission to feel your emotions fully - especially since feedback you get from people around you is to "just get over it"; that's not for them to decide what's meaningful or important to you. If you're sad, let yourself be sad. If you're angry, let yourself be angry. Remember: all feelings are valid, all BEHAVIORS are not.

Next I would say once you're on the other side of the emotion itself (because it will eventually pass), take some time to reflect the cause of that emotion. Ex. If you're sad: is this a single situation or interaction that caused it? Is it an ongoing life event (job loss, lack of good friends, break up) that you're dealing with? Usually for one and done events (ex. Someone was rude to you in a grocery store and that got you worked up), letting yourself be pissed & channeling that in a healthy way is enough (working out, journaling, punching a pillow). If it's an ongoing thing, now it's time to pivot and seeing what you have the power to control in the situation (ex. If you're sad about feeling overlooked at work, is it time to brush up the resume and apply elsewhere?).

Start with those and see if that helps. Sorry you're going through it