
Hi Lisa
firstly, can I just say what a great owner this lad's finally managed to get - well done to you and your OH for giving a fresh start to a dog which has clearly had a horrible life.
You may well have your work cut out here - more because this dog has by all accounts had very little worthwhile in his existence until you came along and it's only to be expected that having "found" you he'll be extremely anxious when you're not there for reassurance. This is made all the clearer IMO by the fact that he's distressed even when your partner is still with him.
Initially I'd try to get him slowly accustomed to very brief periods of being unable to linger around your feet etc - perhaps behind a baby gate with him on one side and you on the other while you prepare food, work on the PC or such like. Ideally in a situation where he can see you and so find solace in that but not physically be with you. Gradually work towards slightly longer periods and then moving from room to room so occasionally outwith his sight but he knows you're not far and wont be away long :) A DAP plug in kept on 24/7 in the room he's most often in and left in while you go about your business should assist with his anxiety a little. It may take several weeks just to make any obvious progress, but once his confidence is boosted by knowing that you're never gone long and always come back he should start to turn the corner and then progress become more rapid. It is getting to that point which will need the most patience but you've clearly got all the right ways about you to do this for him :)
It may be that you would be best when leaving him alone to not leave him access to your bed - he's possibly "digging" there more than he would elsewhere because it will be the mostly strongly scented area for his "absent mum". By all means leave him an unwashed and worn t-shirt or PJs of yours etc in for eg a bed or on top of a fleece inside the kitchen so he has the comfort of your smell but doesn't feel he has to disinter you ;)
I wish you all the joy and good fortune in the world with this special boy.
I HTH a bit, Teri