-This one is dependent on where you live, but in my area it's not illegal: as a last resort, I smoke cannabis before bed. It's not ideal because it makes it harder to wake up in the morning, but I use it in situations where it's really important for me to get to sleep. Not good to use it too often though, or it stops working, and you can also start to have different anxiety issues as a result of being used to being sedated all the time, as I'm sure you know if you have experience with any kind of tranquilizers or anti-anxiety medications.
In my experience, weed will help, but only if you mix it with tobacco. Weed is an upper, tobacco a downer, and the combination makes you stoned, which can help you sleep. Pure weed on the other hand, could just as well do the opposite, and keep you awake and gaming through the entire night XD.
This is not quite true. There are different chemicals in cannabis depending on the type you have. In most cases, it's a sedative. Most varieties make you very sleepy and relaxed (I can have a tiny bit and find it impossible to stay awake no matter how hard I try) while only very few make your mind active. On the other hand, tobacco is not a downer. Nicotine in tobacco is both a sedative *and* a stimulant which can cause anxiety and keep you awake. How you respond to it depends on your brain chemistry, how much you have, how quickly, and whether you're addicted (if you're not used to it, it will have a strong stimulant, not sedative, effect). And there is the most dangerous part - nicotine is one of the most addictive substances on the planet. I do not recommend using it to try to cure anxiety.
In any case, it's likely that our dear OP lives in an area where cannabis is, unfortunately, illegal despite its myriad medicinal uses and complete non-toxicity. And I suspect Toady would probably prefer we not discuss this particular suggestion too much on the forum because of how many places it is not legal.