The variety of answers here shows one size does not fit all.
Some of us adjust, some don't.
We sleep with windows open on a "local" main road without problems - the first few weeks were difficult until we adapted but we soon didn't notice the noise.
My new neighbour's dog's regular and persistent barking problem is , however, much worse than traffic to us! It spoils our meals, makes us cross and although they are trying to address it, it is for some reason, horrendously disruptive.
If this was in the village where we used to live (a hamlet really), it would be just as stressful.
Do please check the pollution levels though. Even 20yards can make a massive difference depending on the lie of the land. That's what we found.
Good luck.