One of the things I learned on retreat is how St. Ignatius really stresses the idea of asking for the graces we need. Every prayer time is supposed to start out with becoming aware of God's presence and then asking for the graces we want. And it's not only asking but even begging!
As I was going through the exercises and would hit certain bumps in the road, my director kept telling me to ask God to help me get through it. And the amazing thing is that he did! The graces really came.
That's something not only for retreat, but for all the time, whenever we pray. Keep asking, keep knocking on that door, keep seeking, like the Gospel says. My director said that God wants to give us grace more than we want to receive it--he's just waiting for the right moment when we're really receptive. It can be on retreat, or it can be at home, while shopping, driving the car, or praying at church. God is so in love with us that he lavishes it on us.