I am 48, divorced, chronically ill, and have already raised my two kids, ages 28 and 30. Now that the phase of my life of marriage and raising children is over, I feel discontent because I want to know my purpose now. I pray all the time about this. How does one know their purpose in life at my stage?
First of all, unless you have received a declaration of nullity from the Church or unless your spouse has died, you are still considered to be married in the eyes of the Church. The Church considers civil divorces to be the equivalent of legal separations and tolerates them when obtained for just cause for the purposes of settling estates and child custody. But unless an annulment is granted or until the death of one of the partners, the couple is considered to be married. Only death can end a sacramental marriage and the Church presumes marriages between baptized persons to be sacramental until determined otherwise. That means that a divorced person without an annulment is expected to observe the chastity required of an unmarried single person.
That said, determining one’s purpose when relieved of many family obligations is not an easy one. St. Francis De Sales and St. Ignatius of Loyola were involved in aiding discernment, so you might wish to read some of their writings. St. Therese of Lisieux also established for ordinary people the means of obtaining holiness through her Little Way.