Last year, I had a manuscript that got a bunch of requests for partials and fulls...and some great feedback from agents for whose services I'd almost kill (I simply cannot end a sentence with a preposition...sorry). That manuscript didn't get me representation, but it gave me hope that I could write something good, something good enough to sell. So where I once saw the inbox and assumed it was another request for a partial, now I automatically reach for my submissions spreadsheet and get ready to log another no.
And what very little feedback I've gotten so far points me in the direction of independent presses...so maybe I'll have better luck there.
And yes, there once was a trembly feeling associated with my inbox. I long for those days...