Hugs to you & Shelby. I've been in you place so understand how it hurts but as others have said, she will tell you. My Sheltie/Spitz was with me until she was 20+ & even thru her having senior moments & not seeing clearly I said as long as she was happy I'd keep her with me which is what I did, she did let me know when it was time & it was the hardest thing I'd done. Just love her for as long as possible.