Hi silent runner, welcome to Psych Central. Sorry you are having challenges feeling emotions. Having a therapist can help sort out what has happened to make emotions all bottled up and find ways to express them appropriately.

There is also an article on why emotions cannot be expressed.
10 Reasons You Can?t Say How You Feel | Psych Central

For me lifestyle changes fit big in my recovery hopes..

I have to watch what I eat because foods I eat can stabilize my moods or exaggerate them. A high protein low carb diet with snacks or meals every 3-4 hours will over time reduce my swings. I also avoid alcohol and recreational drugs because those can really increase depression.

Other lifestyle changes that help me are doing yoga, exercises, mindfulness, calm music, and being active on Psych Central.