OP DH and I have both had long careers in investment banking. I can relate to the shock and fear you’re feeling as getting made redundant from a very high earning IB career is part and parcel of the job. I have seen hundreds of high earning investment bankers made redundant over the years, including me twice and DH twice.
Some of them find another job for a few years then get made redundant again, for others, it is the end of their high earning careers. DH spent a couple of years out of work, followed by a stint working in a pub, before managing to find a job in compliance, earning about a quarter of what he used to earn. It does change the direction of your life, of course, but you need to try and reframe this. You’ve had many years of earning well, presumably you’ve been able to buy a house, have some pension savings, been able to enjoy some nice holidays? In the worst case scenario, this phase of your life may be over and now you’ll have a more ‘normal’ life. It may mean your child needs to leave private school, which feels devastating, but please try to focus on the positives a few years of high earning has given you. High earning jobs do usually come to an end at some point - think about athletes hampered by injuries in their prime, actors getting ‘cancelled’ because of something they’ve said or done. I knew a fair few of the bankers who left Lehman Brothers carrying their belongings in a box. For some of them, no, they didn’t get another banking job, but they have gone on to have happy and fulfilling lives nonetheless.
It doesn’t detract from what you’ve achieved but you need to focus on your new ‘normal’ now and what that’s going to look like. The first step in that, is deciding if you’re not going to work in your old sector again, what would you like to do instead? I took an admin job in the legal team at HMRC, ultimately, it wasn’t for me, and I’m actually now back in IB, but having that job whilst I looked for another IB job restored my self esteem and stopped me from spiralling (which is what you’re doing), I also looked at admin jobs in schools. I saw it as an opportunity to try out some new jobs, whilst I worked out what my next phase would look like.