When the demons expel self-restraint from your intellect and besiege you with thoughts of unchastity, turn to the Lord with tears and say, "Now they have driven me out and encircled me"; "Thou art my supreme joy: deliver me from those who encircle me". Then you will be safe. (Maximos the Confessor)

Maximos is writing principally for monastics. But many of us undertake vows, formal or informal.

Vows freely undertaken should be honored. Longing for sensuality, sex, and success can complicate relationships with God and neighbor that are our core purpose.  Choosing to put such longings aside can, for some individuals in some circumstances, clarify and simplify.

We will not, however, keep any vow of our own accord.  If we persist it will be, as Maximos counsels, with God's help.  When we fail - which is likely - we can be restored through God's grace.