I am very sorry for the loss of your beloved dog, and your other terrible losses.
I agree with others, sometimes people don't know what to say in the face of death, although I think your friend was just unkind, to say the least.
It is very difficult to feel alone. I do have friends and family, but they are busy with their own stuff and are not always available, so I think I understand what you may be feeling. I'm working on learning to be resilient, to cope alone, make decisions alone, and to practice self love. It's a work in progress, but it is doable in sobriety.
SR is a wonderful place. I hope you may decide to stay. Best wishes.