Happiness is a state of mind which is unattainable in a sense that one cannot remain happy all the time.Some matter of the other is bound to get stuck in one's mind and pester it,producing negative thoughts or thoughts which signify hopelessness.This is only natural and human to feel this way.
We need to understand that life with all it's nuances can never be 'fair' according to us and keeps hitting us with harder stuff than the last time to make us stronger and better.
The need to want more will never end professionally as well as personally.But,if we are not satisfied or happy with what we have,what makes us think we will be happy with more?
In the course of life,we sometimes let personal issues slip in the name of ambition and money.This is not a healthy habit as if one is not emotionally stable one cannot perform at one's fullest professionally too.It's important to address all issues pestering one.They should be addressed one at a time or they might cause trouble if taken all at once.There's no problem without a solution so we should always try to remain optimistic and be the person who sees the glass half full rather than half empty.I feel this is the only true way to remain happy most of the times.