What an amazing story!
I understand the author is not the person who was friends with Clara. Whoever she is must understand that losing a child is the worst thing that can happen to a person, and the changes that occur after that death need never be dwelt on.
I am so sorry for her loss.
Before that, her relationship with Clara was such that she made no room or effort for anyone else. Sadly she had no power to make the time she had for Clara precious. Clara knew when she called her friend, that person was always available.
Working for my father in his business from 12 to 21 was the thing that made me social, and I learned to love meeting new people and talking to them. I understand that it isn't the same for most people.
Here is what I see. Clara is always looking for the next interesting new person and adventure or focused on the future. Reading about the subject of the story tells me she is stuck in the past with this person. (all before the passing of her child)
Now that she will be in grief mode for a long time, and it will be something that will hurt forever, she should not care who comes and goes. She needs to care for herself and find a path through it all with therapy and perhaps psychiatry.
If Clara comes back, give her limited space in your life and mind.
Respectfully, Will - Father of 6 grown children who lost his first wife and deep love about 10 years ago.