@Connie *********
are you under doctors care for your medical condition here in Thailand?
If so consult with your doctor about a no fly ...under medical care extension...usually granted up to 60 days.
A 90 day extension requires additional hospital documentation.
That would give you from July 31 for 60 days to see if a land border opens. If it does...doing border runs with extensions ..30 days plus 30 day extension...will get you to your 50th birthday in December. Two land border runs are allowed each calendar year.
You have options to consider...Good Luck