Hello Angel2, welcome to gransnet. Its a bit addictive though, so beware.
So sorry to hear about the loss of your beloved whippets, and what a blow to lose two within such a short time. I posted on here recently about the loss of my beloved little cat Panda over six weeks ago now. Everyone is so understanding, and posted some beautiful messages. I found much comfort in messages from like minded folk. Regarding your inquiry about chocolate labs, I have a neighbour who has one, although his temperament is gentle, (the dog I mean) !! he seems to give them a few problems in that he is very strong, I often meet them out walking and they look exhausted being pulled at a rate of knots. Dont know whether this is lack of training or just a strong willed dog taking advantage of his owners.
Good luck with your search. 