Being sick is not easy, especially when that sickness lasts an extended period of time.
Typically our only concern is to get better, and everything else in our life, including our faith, can be negatively impacted.
St. Francis de Sales offers some sound advice in his Introduction to the Devout Life to anyone suffering from an illness, giving a few key things to keep in mind.
Offer your suffering to God
When you are sick, offer all your pains and weakness to our Dear Lord, and ask Him to unite them to the sufferings which He bore for you.
Take your medicine
Obey your physician, and take all medicines, remedies and nourishment, for the Love of God, remembering the vinegar and gall He tasted for love of us.
Desire your health in order to serve God
Desire your recovery that you may serve Him.
Accept a terminal diagnosis and look forward to Heaven
[B]e ready to die if He wills it, to His Glory, and that you may enter into His Presence.