Tips for wispy/oily hair?

I have thin hair that’s been severely affected by a combination of insomnia, high stress levels and anemia. The two pictures below were taken 3 years apart (the latter before any of these 3 problems were a thing). The day of/after I wash my hair, I have massive amounts of flyaways and wispy hair, and the after that one it gets so oily it always presses flat to my scalp. I don’t know what to do anymore, I’ve tried a bunch of products and talked to my hairdresser but nothing seems to work, it either dries it out to an extreme or makes it impossibly oily. Any ideas?