My next door neighbor at my old house had exact this: a very bright streetlight sort of thing that shone directly in our bedroom window. I bought "blackout blinds" (cellular blinds that have foil inside, so light simply doesn't get through). That was sufficient to make it livable from my bedroom, although it was far from ideal.

I did talk to my old neighbors about this several times. They basically weren't amendable to doing anything.

As a long-term measure, I planted some trees in the way, that would eventually have blocked the light. I sold the place before they got big enough to do much good. Next time I'm faced with something like that, I'll be bringing in bamboo or something else that grows really, really fast.