I have had intense sleep related issues through life, usually related to my current stress level but not completely debilitating. Its always the thoughts that won’t turn off, it seems the more pressure to get the rest when you need, the more the mind wonders and won’t shut down. I can tell you the few things that have worked at different times. No one particular thing had worked every time unfortunately. First, talk to a doctor. Yes, at times sleep aids and anti-anxiety medications were needed, just be careful. Sometimes reading for fun will work. I know if you’re in grad school addtl. reading doesn’t sound desirable BUT if you can remove the racing thoughts it occupies the mind enough to fall asleep. Sometimes it’ll make you feel so sleepy, it’s almost feels like a sleep-aid. Also, yoga daily can center and quiet the mind, or mindful meditation. You also might want to do a little self reflection. Ie: what’s causing the heightened anxiety? Maybe you’re worried about graduating, I was. Also, looking at what road to take after graduation can be overwhelming, journaling might give you clarity. And if you’re tossing and turning, get up, do something interesting to you( like paint?). At the very worst if you aren’t sleeping, you’re doing something cool. I really hope I’ve given you some ideas. Best of luck and congrats.