=D we see this a lot with Westin, also. And I have two theories about our puppy! lol. for some background info, Westin LOVES to play with my boyfriend.. he runs and fetches and barks and hops around. For me, he lays at my feet and is very mellow, I think he just likes the petting he gets!
1) it is VERY possible that Westin likes Jim better...
but I doubt it.
2) we have very different styles of "playing" with the puppy, and he is just adjusting to the both of us, which might be what Snickers is doing with both of you!
Also, it is VERY possible that she is just tired. Westin just spent three days at his "cousins" house while we were on vacation and he slept for a full day before he got "rested" enough to play with us! With the other dogs around, it might just be that they don't give her time to take the naps she needs (and Westin takes A LOT of naps!) and so she just wants to rest when she gets home to you! If you keep her home on a weekend, I think you'll see a huge difference!
I hope this helps! ((and I hope to see pictures of Snickers soon! She sounds like a lovely tri-colored corgi! =D))