It is OK not to receive Holy Communion. There could be many reasons. Perhaps we did not get a chance to fast for one hour. Perhaps we are not in the state of grace. Perhaps we are concerned about sickness. Perhaps we are physically separated by distance. The Church has a whole area of devotion and prayer called “Spiritual Communion.”
Spiritual Communion is done when a person is unable to make a Sacramental Communion. Since there is no physical reception of the real, true, and substantial Body & Blood, Soul & Divinity of Christ in a spiritual communion, then there is no reception of sanctifying grace, only actual grace. While Canon Law only permits someone to receive Holy Communion no more than twice in one day, a person can make NUMEROUS spiritual communions all day long.
We can make a Spiritual Communion during Mass or before our Lord in the Blessed Sacrament, or anywhere else where the Spirit moves us. Here is a prayer that may assist in making a spiritual communion when we are not able to receive.
Spiritual Communion Prayer
My Jesus,
I believe You are really here in the Blessed Sacrament.
I love You more than anything in the world,
and I hunger to receive You.
But since I cannot receive Communion at this moment,
feed my soul at least spiritually.
I unite myself to You now
as I do when I actually receive You.
Amen.