Life is not hard, but, unfortunately, we make it hard. Even though we have everything to enjoy this moment, we suffer instead. For instance, consider a moment when we are unhappy. It is not because we have something lacking, but because we live in the past or future. 

Let's consider a moment we are at a hospital because of sickness. At a time like that, what we need is medicine and rest, which is what we have in the hospital. There are doctors and nurses to take care of us when we need them. They are well-trained; they know what to do, and what not to do. We can rest and relax. We should not worry about anything. However, what we do is, instead of relaxing, we worry about our relatives, friends, careers, and/or money, etc. Because of that, the healing time gets long, and the stress goes high. 

The physical pain is there, that's why we get treatment. Instead of physical pain, we have added so much mental pain too. It is too much. Thus, we fail to enjoy life because of this additional pain. 

If you consider the current moment, you could enjoy and relax, which helps you to increase the healing possess. 

The truth is like this in a painful moment, so nothing to say about normal life. The choice is yours, If you want to think about the past or future and suffer. Or you could think about the present moment and enjoy life. Enjoy the present moment.