I hear you - been through that so I can relate and empathize. This is probably why I don't make friends easily - mainly acquaintances because I am aware not everyone will have your back or stay with you at the slightest sign of bad weather - In other words, I have no need for fair weather friends
I think one of the reasons is they don't know how to handle a difficult situation and think it is best to stay away or they are too selfish - I mean everyone has their problems and ours may not register high on their list....and so on...
I think it is when friends are struggling that you need to stay the closest and let them know you're there for them