i am sorry, but i cannot accept any more dogs into my home (permenantly). have you considered a breed rescue? then you can keep in touch with the dogs new owner, and you know that they are going somewhere that knows what to expect from a dog like a newf. (or a terrier for that matter!) i have a Westie and a newf cross, along with a akita mix and a dachshund mix, so i know a little how you feel. i am SO sorry that you have had to make this decision, and personally, i think your cousins husband is a jerk, and he should understand if he is a dog lover.
anyway, i hope this has helped, and good luck!
Leah