This Is No Time For Unbelief
So, it is possible to legitimately doubt the Indefectibility of the Church?
No, of course it's not. Not if you call yourself a Catholic. Actually, strictly speaking, not even if you don't.
Come on, people. The first Pope denied Christ. Only one of the Apostles was at the foot of the Cross. If you feel abandoned by your bishops, know it has happened from the start.
The Indefectibility of the Church is, besides being de fide, brilliantly demonstrated by the tragic events, the desertions, the betrayals, the cataclysmic upheavals that have marked her existence since the very start.
Man up, and believe all that the Church believes.
This is not the time – if there ever is a time – to lend legitimacy to unbelief.