I recently adopted a 10 year old named Marley. I previously had a one year old cat named Noelle. Introducing them has not been the smoothest. Marley has ran out of her separated room a couple of times when we opened the door so they have come face to face. The new cat Marley hissed at the resident Noelle which was worrying because I thought it should be the other way around. I know the process takes time and patience but Marley hates being seperated of course we pay her many visits but you can tell shes miserable in there. She has a scratching post and toys but is not interested. We let her out and let Noelle into her space once or twice a day. She has began skipping out on meals when we first got her she would devour her food quickly. I'm worried about her health. What should I do?