Mac OS upgrade - Photos library won't work

[tjscraps]

Help! I upgraded my Macbook to Catalina and now my Photos library won't work, it indexed it the first night and it was working, then I closed it and reopened, now it's been stuck 'recovering' for hours, stuck at 0%.

Anyone have any ideas? I've googled but haven't found a solution. I do use iCloud for photos I'm wondering if I delete the photos library if it will delete from iCloud too? Literally ALL my pictures are in there - backed up to iCloud and BackBlaze, but it doesn't do anything when I can't open the file! I can see the photos on my phone still.