I do not need comments about how stupid I was to allow them to get where they did, what I need are suggestions where to go from here.
Absolutely so.
You've done the obvious - closed bank & other accounts.
Think carefully about what other info they may have gained from you, directly or inadvertently. For example, your credit cards. Any remote chance that these were compromised.
What about passwords? Were you asked for any, directly or otherwise?
They have your email address, obviously, and maybe some additional info such as your DOB; perhaps even your home address?
In addition to closing as many avenues into your life as you can, I'd suggest that you run some tests on your Mac to see if they've left behind any Malware.
Download Malwarebytes anti malware app from here:
https://www.malwarebytes.com/free-multi-os-download/
Install it. Ignore the "free trial" offer. Pay nothing. After 30 days, it will continue as a free app.
Now run the app and quarantine/destroy any malware found.
After all of that, I'd be inclined to download a clean version of whatever OS you are running.
To do this: reboot the Mac whilst holding down Command + R. This will take you into Recovery Mode where you can reinstall your current OS. This Apple article adds substance to what I've just said:
https://support.apple.com/en-gb/HT201314
Please post back. I am very sorry that you have suffered this fate.
Ian