My 16year old Lhasa was diagnosed with mammary cancer in 2005 she has an open wound on her stomach that won't heal and is getting bigger, she doesn't seem to be in pain but she sleeps all the time This is killing me I know that she is "just a dog" but I love her so she has been a loyal friend I dread putting her down to early and my husband won't help me in making this decision I don't want to extend her life selfishly.Any advise?