"For I say, through the grace given unto me, to every man that is among you, not to think of himself more highly than he ought to think; but to think soberly, according as God hath dealt to every man the measure of faith." -- Romans 12:3
Every page of Scripture resonates with the same sound -- His will alone.
2Pe. 'that none should perish'
As for Romans 12, please look at the context.
Is Paul speaking to the unsaved or saved?
He is speaking to the saved and exhorting them to the Christian walk (why the exhortation if God is doing all the work anyway)
All Christians do receive a measure of faith at the point of salvation and it is up to them to make it grow (2Pe.2:2,Heb.5).
So in your Christian walk, God makes all your choices for you, including the ones to sin?