2 Corinthians 10:4

​The weapons of our warfare are not carnal.."

In regards to doubting, or feeling alone. 

You never know how much you can take, until God puts you in a (position) or situation to show you that you can take much more than you (thought) you could. 

And then you will be in the position where you will (see), He was (always) there.,

2 Corinthians 10:4