Sorry for your loss. Sounds like he was a lovely cat. I'm sure you'll miss him for a long time, but I hope it gets easier with time.
We thought we'd lost our cat a few months ago after she had what turned out to be a stroke. We all said goodbye as my wife and I took her to the vet, not expecting her to come home. My kids were distraught. Consequently when we brought her home they were overwhelmed with joy.
I fear it was a taste of things to come, as she's very old. Not looking forward to going through all that again.
I've just read the thread to the end and now see you have an addition to the family. Congratulations!