I think the very best thing that one can do is remember that there have ALWAYS been times when the Christians were 'in the catacombs', that is, there have always been periods of history when Christians were forced to hide, to do without the public worship, to 'make do' with the circuмstances that they were faced with.
Remember, too, that God instituted the MEANS on earth for us to receive His graces, such as Holy Mass, etc, but those graces cannot be gained by people whose HEARTS are wrong before Him. Call to mind how God the Father said in the Old Testament that the people 'draw near to Me with their lips, but their hearts are far from Me'; Our Lord Jesus echoed those words when he spoke to the Pharisees.
What I mean to say is that we could have every freedom, every resource and every opportunity to receive the Sacraments and still have attitudes that do not befit a Christian. Take, for instance, those who flooded the Council with their heresies and tried to establish a New Order that would do away with the Faith. NOTHING short of a total conversion and repudiation of their former actions and beliefs would make those heretics worthy to receive the Sacraments. They do not, in their souls, WANT the things that Christ Our Lord intends to give His people in the Mass, so even having ten TRUE Masses a day at their disposal would do them no good.
Those who are faithful to the Church and to Christ and Our Lady, however, CAN and DO receive God's mercies and graces, even when they are FAR from a place where the true Mass is said. In times of dire emergency, one can receive Christ spiritually when it is impossible to be with Him in the Eucharist at the Mass.
Take my case, for instance... I live nearly TWO HOURS away from the ONLY independent traditional chapel in my state. Their website is down, there is no phone number available for the chapel, and the email address that was listed is from years ago and is no longer valid. It belonged to people who left a diocesan church and supported a traditional independent priest, but it all happened years ago.
I have NOWHERE to go in my region except a 3-hour drive to a trad church in PA, or similar trips to other places in other states. It is out of necessity that I pray every day to ONE DAY be ABLE to be baptized a Catholic and receive the Sacraments. I have absolutely no other option right now. I couldn't afford even a ONE-WAY trip to any of the traditional locations in my region, as I am unemployed and have no savings.
It stands to reason, then, that even if there comes a time when there simply are NO places for traditional Catholics to go to receive the Sacraments, that we can still rest in the knowledge that God will sustain us. Frightening thought, to be sure, that there might be NOTHING on the landscape for us, but a real comfort to know that none of it is out of God's control, and He will NEVER let His Church disappear.
Our Lady, Help of Christians, pray for us.
Sacred Heart of Jesus, have mercy on us.