Do you often question yourselve about this? We face so many obstacles day by day. It takes so much courage to overcome it. Fear not, all of the answers are already stated in the holy Quran. And all you need to know to understand the meaning behind those answers. Take a look.
1. Why are we tested?
Do the people think that they will be left to say, "We believe" and they will not be tried? 
But We have certainly tried those before them, and Allah will surely make evident those who are truthful, and He will surely make evident the liars. 
[Al-ankabut verse 2 and 3]
2. Why can't I get what I want?
Fighting has been enjoined upon you while it is hateful to you. But perhaps you hate a thing and it is good for you; and perhaps you love a thing and it is bad for you. And Allah Knows, while you know not. 
[Al-Baqarah verse 216]
3. Why is this test so severe?
Allah does not charge a soul except [with that within] its capacity. It will have [the consequence of] what [good] it has gained, and it will bear [the consequence of] what [evil] it has earned. "Our Lord, do not impose blame upon us if we have forgotten or erred. Our Lord, and lay not upon us a burden like that which You laid upon those before us. Our Lord, and burden us not with that which we have no ability to bear. And pardon us; and forgive us; and have mercy upon us. You are our protector, so give us victory over the disbelieving people." 
[Al-Baqarah verse 286]
4. Why do we feel frustrated?
So do not weaken and do not grieve, and you will be superior if you are [true] believers. 
[Al-Imran verse 139]
5. How do I face this difficulties?
And if you brought to those who were given the Scripture every sign, they would not follow your qiblah. Nor will you be a follower of their qiblah. Nor would they be followers of one another's qiblah. So if you were to follow their desires after what has come to you of knowledge, indeed, you would then be among the wrongdoers. 
[Al-Baqarah verse 145]
6. To whom, do I rely on?
But if they turn away, [O Muhammad], say, "Sufficient for me is Allah ; there is no deity except Him. On Him I have relied, and He is the Lord of the Great Throne." 
[At-Taubah verse 129]
7. What can I get from this misfortune?
Indeed, Allah has purchased from the believers their lives and their properties [in exchange] for that they will have Paradise. They fight in the cause of Allah , so they kill and are killed. [It is] a true promise [binding] upon Him in the Torah and the Gospel and the Qur'an. And who is truer to his covenant than Allah ? So rejoice in your transaction which you have contracted. And it is that which is the great attainment.
[At-Taubah verse 111]
8. I can't bear with this calamity anymore!
Send him with us tomorrow that he may eat well and play. And indeed, we will be his guardians. 
[Yusuf verse 12]
9. Until when must I stay strong?
For indeed, with hardship [will be] ease.  Indeed, with hardship [will be] ease. 
[Ash-Sharh verse 5 and 6]
Allah has answered every single question that we need. And all it takes is for us to read and search from the Quran. As a Muslim,ask yourself : What legacy are you working on before you leave Dunya. Do you even have a plan? From now on, work for it! An only rely on Allah. Imagine how pleased He will be when you only refer to Him as the only solution.
19th Ramadhan 1433.