Take a look at your own life. You have gone through and come out of many problems, which you had thought were impossible. It appeared to have shaken you at that moment, but later on you found that you were as complete as you were before.
If you have a problem now, realise that this too will go because you have the energy and power to overcome it. Do some breathing exercises and meditation to stay calm. And most importantly, have the confidence that you will be helped ---a power in the universe is going to help you.
You cannot imagine how much you are loved by God. No more doubts about that, and no more self-doubt. In the Bhagavad Gita, Lord Krishna says, 'When doubt enters into the heart of an individual, he is totally lost, and he becomes miserable."
A discontented or grumbling mind, even if it gets everything on this planet, will still remain miserable. Purity, clarity, and contentment is the formula for happiness.
If there is lack of contentment and you are complaining and grumbling, then you should become aware of it and snap out of that state. Do everything happily. Walk, talk, sit happily; even if you complain against somebody, do it happily.
Nature will put many events in your path to shake your faith, but even then if your faith still remains then you have become a really perfect person, and things will move smoothly.
If you keep your mind quiet at small intervals, you will be able to establish connection with God. Then, whatever you desire and wish for, will be fulfilled. It may take some time for it to be completed, but it will happen. God isn't in the sky somewhere; He is residing in our hearts. And if we cleanse our hearts, then the Divine will-power will emerge from within us. One only needs to have patience and faith.