What's the matter with Eddie?

This is my Eddie. Carefree, joyful, playful. The dog that thinks EVERYTHING is fun!

Like grass-rolling.

He is always bright and alert.

With green pond slime on his chin.

But something has happened to my Eddie's joy, and I don't know what to do about it.

This is him lately. Sullen, withdrawn, pitiful.

I've looked up information about depression in boxers and, shockingly, there was quite a bit of information. I didn't think it was possible for that kind of joy and cheerfulness to be hindered. There seems to be several reasons that dogs get depressed like;

Separation anxiety

loss of a playmate

a big change like a new home or different schedule

loss of an owner

We haven't been through anything traumatic really.

He is still eating and drinking well, but he just seems so so sad. It really makes me want to cry.

This is the face he made when I said, "you ready to go??" Which always perks his ears up and puts that excited, happy smile on his face. But, this was his response. I even threw his ball for him yesterday and he just stood there. Maybe it's the heat?

This has been going on for a little over a week now. If anybody knows anything about this condition, please let me know. All the hugs and kisses and poor babies haven't helped. If he doesn't improve soon, I will take him to the vet just to make sure nothing is physically wrong with him.

For now, I will just keep trying to cheer him up. It is the least I can do for all the times he has lifted my spirits.