Put the glass down.
If you don't know, this refers to a technique you can use to let go of bad thoughts long enough to get to sleep.
Imagine holding a glass of water in your hand while reading this thread. Feels easy enough to hold, right? Now imagine you have to hold it for half an hour. Your hand is getting tired. Imagine holding it for the rest of the day, without ever putting it down. Your arm would burn and your muscles would shake.
Worries are like holding the glass. Your mind can cope with them for a little while, but the more your hold onto them the harder it gets.
Tell yourself that you can put the glass down. You can shelve these intrusive thoughts until tomorrow. You allow yourself to unpack them and look at them, let them breathe for a bit and then make a conscious choice to put them back in the box.
The crucial element here is that you promise yourself that you are allowed to look at them again tomorrow. They aren't going anywhere, you can come back to them anytime. It's this part that helps to break the cycle because the thoughts stop being forbidden or taboo, so the unconscious brain is less tempted by them.
I do this often when I have a really difficult patch in life and I've always found it works if you consistently practice it for a good stretch of time like a couple of weeks.