You could be describing me! Feeling like you're losing it is a perfectly natural reaction to dealing with that numb feeling day after day. Sadly, I haven't found a way to get rid of it, but I found that for me, at least, getting more sleep than normal (10-12 hours) helps a little.

You said you can't stop thinking about certain things. If they're causing you stress, maybe it would help to write them out here, or if you're not comfortable with that, maybe write them in a journal.

I know it can feel like you're the only one who feels numb, but trust me, you're not. Even if coming together here only helps a little, it's worth it.