The bigger the dog, the shorter they tend to live. If you love big dogs, I would still get a big dog. Some toy-sized dogs will die early. On the other hand, we have a mastiff that somes to the clinic, and she's 15 this year and isn't even slowing down much. And also, whether it's cancer, kidney failure, or some other dsease, it's hard to watch - that's just a part that, unfortunately, comes along with letting pets into your heart. All you can do is prevent what's preventable - you have virtually no control over the other stuff. I'll tell you right now that one of the worst things is to see a dog gying from heartworms - such a terrible disease with such a simple prevention. With cancer, you can't really prevent it. We just out down a golden retriever yesterday who had lymphoma. A year ago, he was fine. Six months ago, he was fine. It all happened within the last 2-3 months

You just never know...
I would wait until you're sure you're ready for another dog (some people are ready for a new one the next day, others take years, it all depends on how you feel about it - don't let anyone tell you it's too early or you've waited long enough - you will know when you're ready) Once you're ready, get whatever kind of dog you like - if you like mastiffs, or labs, or great danes, or boxers, then get one. But as you surely know from experience, sometimes the best dogs are mixed breeds - and it feels wonderful to give a shelter dog a home for life
