One book, The Spiritual Life: A treatise on the ascentical and mystical theology has some points to make about angels.
First, we often forget that angels are a part of our spiritual lives…they are there to help us on our lives of faith. Each of the Angels reminds us of God, for each one in some way symbolizes Him. Some his love, others his strength, some with power, etc.
They are there to help us through the process of sanctification.
And the Angels we celebrate today, the guardian Angels, God has commissioned with the care of individual souls.
God uses these Angels to unite the Church Triumphant and the Church Militant: “He sends this mysterious host of Angels in order that they may be uniting themselves to us and binding us to themselves from one body of the Church of heaven and the Church of earth.
And so, “our Guardian Angel keeps us in constant touch with heaven.”
The book tells us we should make our Guardian Angel “the object of our veneration, our confidence, and our love.”