Wow, what an amazing trip you've been on. If you need to stop, just know that what you have done is a great accomplishment, and you will carry it with you forever! I'm really in awe, what a great way to see the world.
A couple of suggestions...
Is there a way you can continue the travel up to Scotland, off the bike?
If you do stop, perhaps you could heal up for a good long while, then finish the last leg of trip in a year or two or five?
Do some sort of celebration, wherever the end is, you deserve it!
Good luck and keep us posted.
2001 Cannondale R500 <3
2011 Specialized Ruby Elite Apex
2021 Tangential Speedarama