When you cannot receive the Eucharist at Mass, the Church encourages us to make an act of “spiritual communion,” where we unite ourselves to God through prayer. It is a beautiful way to express to God our desire to be united with him when we are unable to complete that union in the reception of Holy Communion.
My Jesus, I believe that You are present in the Most Holy Sacrament. I love You above all things, and I desire to receive You into my soul. Since I cannot at this moment receive You sacramentally, come at least spiritually into my heart. I embrace You as if You were already there and unite myself wholly to You. Never permit me to be separated from You. Amen.