I have 4 feral cats that i rescued and have had ...

I have 4 feral cats that i rescued and have had them for about 3 years now.  One of them is a scardy cat and gets picked on all the time by the other 3.  When it comes to feeding they all come together rub heads and act like he's their best bud, but after the feeding, he is run off and chased from then on.  He never comes out during the day, stays hidden and never associates with the others.  He has also urinated on my bed on my husband's side, so i'm afraid to have him in.  He has a litter box to his exposal whenever he needs it, so their is no excuse for the bad behavior.  I have never had cats in my life.  I bought the book the cat bible (everything your cat want's you to know).  It's been helpful to some extent, but it's not so good for feral cat info.

I'm just beside myself because he is just such a loving cat.  His circumstances were bad for him, but i have tried everything that i know of, read about, was told.  He is also pure black so finding him a home is worrisom.  I've heard terrible stories about what people do to black cats.  I just don't know if this cat is happy or what.  With hiding all the time, not so social, i'm also wondering if i'm doing him and injustice? Maybe it's just me and i'm being overly sensitive.  Please help!!!! 

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