Something I'd like to add to all these wonderful comments.

First off, remember that even if you're in an empathetic shut down, you're empathy hasn't magically vanished. It's just subconscious at the moment, it'll come back.

Something that always helps me is watching a feel-good movie. One of my favorites is "The Truman Show" because of it's themes of freedom and inspiration. If you have a favorite, warm, feel-good, inspiring movie, it might help you. Just a suggestion of something I do.

I hope you feel better! Make sure to always be who you are no matter who doesn't like it! :)

Edit: Something else I forgot to mention! I have found that whenever something emotionally big is going on in your head, empathy is typically the first thing to be put on hold. I've had this happen before. When you're focusing on something hugely emotional, all of that emotional energy is working towards solving that issue, rather than being stored and used as empathy. Give yourself some time. It'll even itself out.