I'm so sorry to hear all the troubles you are going through with all your best buds .... and I'm sorry to hear about Lex ...
In 2008 I had 4 small dogs and all were quite close in age in July of 2008 one was really sick and loosing body mass so I took him to the vets who told me that he had cancer all inside of him so I had to put him down he was 15.. and we called him Bud .. less than a week my other one who was 13 had a real hard time breathing so off to the vets again emergency and she also had to be put to sleep ....In Dec that same year another one of my pups who was 16 had to be put down ... when you have multiple pets for a long time and all of a sudden you are down to 1 ... man its like someone kicked you in the stomach. I swore that I would not get any more for a while and stick with just the one I had left .... my little cocker Sadie..... but you know as time goes on you forget the sadness and remember the good times and everything good about them and you move on .....
It just seems to me that we do not find our animals but our animals find us .. How lucky are they and us ! I now have 5 and all close in age and I know that I will go through all of this again but its sooooooo worth it for everything they bring to us..
Again my condolences .... for your loss .... RIP