Food and shopping are not true joys.
Rabbi Nahman of Bratslav, Liqqutey MoHaRaN 2:23
Regarding joy, a parable: Sometimes when people are happy and dancing, they grab hold of somebody who's standing outside, being sad and melancholy, forcing him to join into the circle of dancers, making him rejoice with them.
So it is with joy. When a person is happy, the melancholy and suffering are pushed off to the side. But the higher way is to struggle and pursue sadness, to bring it into joy in such a way that melancholy itself is transformed into gladness, so that all the sufferings become joy. That's the way it is when you really enter into joy; the elation is so great that you change all your worry and sadness into joy. You grab hold of that melancholy and force it into the circle, as we said above.
This is the meaning of: "Joy and gladness will catch up as woe and sighing flee (Is. 35:10)." Woe and sighing run away from joy; their way is to stand off on the side. But you have to run after them, catch up with them, and make a point of bringing them into your joy. Gladness and joy need to grab hold of that woe and sighing, forcing them, against their will, into the circle. Sometimes woe and sighing are the "other side," the part of us unwilling to become a throne for holiness. That's why they run away, and why we have to pursue them, bringing them into holiness, meaning joy, even against their will.