Surrendering to God is difficult, but once you get started, it becomes easier and easier. That's because when you open up to God, the Holy Spirit is able to start working on you. (It's back to "Say OK to God and he'll take care of the rest.") As time goes on, you sense more of God's beauty, taste more of his sweetness, and you open up even more. Eventually, you will want all of God, desiring full union with him. (The Holy Eucharist, God's greatest gift of himself and the treasure of the Church, is absolutely necessary to achieve full union.)
Basically, don't struggle on your own; just be open and passive. Remember that God is love and he is mighty.