9yr old male cat sick or depressed?

My cat has been throwing up for the last ten days. It is a brownish colour, just liquid. He has lost weight can feel his bones. His fur has lost its sheen. He doesn't pur when I pet him. He used to pur so loudly we would have to turn tv louder lol.
We are in process of moving had a Siamese and she hasnt come back in 11 days. Winston grey tabby my cat has been throwing up since then....vet or no vet? Something more serious than depression? Thoughts.

Vet, ASAP! Cats don't throw up from being depressed. Please get him to a vet now.

Totally agree needs to see vet ASAP

I know denial. I don't want anything to be wrong with him. Cat adopted us few years back and he had same signs as Winston does. The other ended up having cancer I have to try and find him now that he heard the cat carrier.

I hope he is okay and it's just something easy to fix.

Please get him to the vet sooner rather than later.  Throwing up for that long is quite serious, he is probably dehdyrated.  Something very serious is going on with your kitty.  I do not think it is depression over the lost cat.  Please take your cat to the vet TODAY.

Took bloof and urine samples, possibly thyroid, pancreatitis or his kidneys! Find out results today. Glad I took him in for sure.

He has kidney failure anemia and pancreatitis.

Oh no!  I am so very sorry you are dealing with this.  Here are a couple of great sites that talk about kidney failure:  http://felinecrf.org/  and http://felinecrf.com/  This talks about Pancreatitis and the current recommended treatment:  Treatment Recommendations for Feline Pancreatitis   I have dealt with both a pancreatitis cat (currently) and a kidney failure cat.  Both diseases can be hard and have their ups and downs but they can survive.  Sending healing vibes for your kitty. 

How long did they survive? From what I've been reading the meds will help for a bit. But there is no cure and with having both he's really sick. He can't even make it to wake me up to go outside, he is trained without a kitty litter. I know the cat we had whom had cancer was peeing everywhere and that was our sign to us he was really sufffering. We put him to rest. It was hard and upsetting thing to do. But he wasn't suffering......