Yesterday is the past, we live for today and expect the best tommorow which is not yet promised.
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You have to live for what today has to offer, and stop worrying about what yesterday and what it took away. The major reason why you keep contaminating your today is because of regret, holding on to the past can really affect our chance of moving forward in life.
You have to let go of what and how you feel life should have turned out and accept the reality of what life is in the present. You cannot change your past, but you can do your best today to change the future.
Waking up today is a miracle and you have been counted as one of the luckiest person to still be alive today, because even those living the life that you expect for yourself just died yesterday and here you are still breathing, it is very obvious that there is hope for you. Be grateful for life, rejoice, live your life to the fullest, do not configure yourself back to yesterday settings, you have been given a new chance to fix things right.
Don't waste your opportunity of life by waking up to yesterday regret. Don't carry your mistakes of your yesterday to today, only carry your goals and aspirations that you have for the future.
Live a purposeful life, not a regretful life.