Have you ever seen an angel?
I did I was no more than 3 months old. I remember her she glowed with a rainbow on her, a pure light, she had pure golden hair and a perfectly white gown. Praise Jesus!
Do you think it's possible that if one prays hard enough that God will send down an angel to comfort and be seen by the person? I mean if there's not one ounce of doubt and complete faith that God, if He wills, will send the angel?
Angels are but messengers of God and nothing else. They are creations of our Lord, who are made to worship God, very much as we are.
I think is sounder to pray to our Lord for His comfort, which strengthens us within. If He decides to send us help through an Angel, that would be cool, but most likely we wouldn't be aware that the person helping us or comforting us is an angel until later.