They also slobber all over the place. The size difference between a bulldog and a rabbit will probably present a problem. If you want to get a dog, it would probably be best to get a smaller one. If you want one similar to a bulldog, get a Pug or a Boston Terrier. In any case, get a more docile dog and one that is small.
Cats get along well with rabbits too.
Of course, you could get another rabbit. In any case, make sure you get a very young animal so that both Spice and his new friend will have a chance to get used to each other without the other pet having any preconceived ideas that a rabbit might make a good meal. As to whether Spice is lonely, that may very well be true. Raising rabbits outside in hutches, we always keep them separated from each other except when breeding. Males will fight other males and females will fight other females.