This is unbearable. I've tried escapism. It does not work anymore.
At least you know you're numb. I've lived a great portion of my life emotionally numb. It didn't become apparent until I had nothing going on that was the case.
I don't think there is anything you can do as a quick fix. If you work 12 hour days, go out, and do a bunch of things to ignore it that only pushes the can down the road. Honestly, you'd have to do a lot of talking about pain. Being in nature may help. Find something that makes you feel connected; or something that forces you to take in every sound, every moment, every noise out in the open. That stuff started to crack my shell but it hasn't fixed it.
I think that unconditional love and acceptance from a real friend may help. Lately I found one person that I can tell 80% of my crap to and that's actually starting to help me validate my feelings. When you feel validated things start to connect.