"The world breaks everyone, and afterward, some are strong at the broken places". - Ernest Hemingway. 

I love this because it says what I have long known to be true - it is not the things that go right that help us develop, mature,and improve.  Rather, it is the adversity, the loss, the pain, and the struggle.  These are the things that form our spirit and allow us to soar.  It is indeed the very things that cause us pain that promote the ultimate recognition and appreciation of the joy life contains.  Life is in constant flux; if you don't like the way you feel you can either change how you are thinking or you can wait, no two minutes are exactly the same and no two days, months, years.  It is amazing that the things I thought were so critical a year ago are now gone from my memory, replaced with today's events.  It is also true that the universe abhors a vacum so when something leaves my life it is only making room for something new to enter.  The strength that comes from breaking is often the ability to maintain hope and the personal knowledge that "this too shall pass" based on actual experience.

Self-Esteem involves our thinking.  Specifically how we think about ourselves, our world, and our place in it.  To improve self-esteem we need to change how we think.  However, quite a bit of what we think is habitual.  And, as with any habit, it takes about 3-4 weeks of consistent effort to change from one behavior to the next.  So, every day for the next 30 days give 5 answers to each of the following statement/questions.  Then, before going to bed, either read what you wrote to someone or find a mirror and look at yourself while reading your list outloud.

List 5 of Your Physical Assets
List 5 of Your Character Assets
List 5 People Who Care About/Love You
List 5 People For Whom You Feel Love
List 5 Things You Did Well Today
List 5 Things for Which You Are Grateful