Sorry I'm late gettin' here ...
I just read over the posts, and to my mind there's lotsa good advice here. In particular, havin' regular lunchtime visits from grandad strikes me as a great idea, if thats practical. Providin' the pup with somethin' Cav-scented could be very helpful too - doesn't hafta be clothes; shoes, boots, slippers, or even hats and/or gloves will work just fine, as might an often-handled tool or even the seat cushion from Cav's favorite chair - if that wouldn't be impractical.
If the pup doesn't already have a private favorite spot, it might be a good idea to see if you can generate one - sorta out of the way, but not really outta the stream of the house's goin's on - a corner, or under a table, somethin' of that sort - stock it with a comfy blanket, a few toys (replacin' em in the spot as they get moved around and left elsewhere - don't interupt the pup while he's at play, unless to join it with him ... just straighten up after him when he's done with whatever he drug off elsewhere) - likely, he'll get the idea pretty soon. An assortment of toys - old favorites and new ones, kept in or near "The Spot" is prolly a good idea - here at Timberland, we have a "Bone & Toy" corner in the mudroom (thats a foyer to city folk :wink: ) - the pups go there frequently to root for somethin' interestin', and when we straighten up the house, any puppy toys layin' around go right back there. Oh, and puppy toys needn't be exotic or expensive either; we've found empty plastic milk cartons and plain old knotted rags are great favorites
I'd recommend a regular routine of mornin' and evenin' excersize - a nice walk (weather permittin', of course, but be prepared to be a little adaptable; the pup's attitude toward weather may differ from your own, and this is about him, after all) every day, twice a day, at roughly the same time and along more or less the same route - while we may find sameness borin', pups appreciate familiar stuff. To a dog, a regular, familiar routine means all is well.
When you leave for work, do so with as little fuss as possible - don't "sneak out" necessarily, but don't make a production of it either. Very shortly, if not immediately, after returnin' from the mornin' walk is prolly the best time to leave for work (the pup'll prolly wanna go relax a bit followin' the adventure of The Walk), so arrange your schedule accordingly. You might wanna get in the habit of keepin' your "grab it at the last minute" stuff - purse, gloves, keys, briefcase, etc - in a convenient near-the-door spot to minimize the departure event. When you get home, the pup'll likely be real excited, but don't go overboard with your own "nice ta see ya again" routine ... be nice, but not overly effusive. In fact, it'd prolly be a good idea to make the pup's evenin' walk a regular part of your own homecomin' routine. Just get the leash and get goin' - don't pause to read the mail, check the answerin' machine, or take a shower. Take care of your own comforts and diversions when the pup's have been seen to - he depends on you. Its up to you if ya wanna leave food available durin' the day - our pups always have access to kibble; they know its always there, dependably, so they don't pig out on it, they just grab a bite or two here or there when the mood strikes - but plenty of fresh water is essential. Make sure the water bowl is big enough to last through your absence, and otherwise keep it full and change it often.
If you're gonna go the dog-walker/pet sitter route, either get plenty of references and let the employee and the pup get to know one another in the home settin' before turnin' 'em loose with one another, or use trustworthy freinds/family already well-known by the pup, if at all possible.
And remember - grievin' is natural - for the both of ya. Let each other help each other through the rough part ... if ya work on it together, it'll go a lot easier - on the both of ya.