I completely agree that you discover your true friends 'when the chips are down'. I first discovered this 25 years ago when my husband had an affair, the children were small and I was pole axed by it and one friend in particular, who I phoned said 'oh yes, and some people talk about it and some don't.' Some friends who I thought would be there, faded into the background.
In life, I've learnt now to see that most people are actually very involved in their own lives, may have had pain of a similar sort which they can't face in themselves, let alone in anyone else and/or they simply don't have space to give you some. In fact, very old friends are often the worst in my experience. I also think the pandemic has dramatically changed how people relate to each other.
Sadly, I also think the UK is now quite an uncaring society, too many years of seeing people on benefits as shirkers and work shy. Even now, the fact that 1 in 4 people are out of work has been labelled as a 'problem' to be solved by getting them back into work as though 35 hours of slaving on basic pay will somehow feel rewarding. As for people, especially young people, being called snowflakes and trauma being reframed as the swings and roundabouts of life and minimised (and that was on All in the Mind, BBC!), words fail me.
Take care, OP, don't expect too much of others and do whatever you need to, to recover a little.