There are no coincidences. There are causes and consequences, and the conditions that allow them. Unfortunately, we are so asleep that we cannot perceive the causes behind all the consequences we experience, nor the consequences of our actions from moment to moment.
"[Karma is] the Ultimate Law of the Universe, the source, origin and fount of all other laws which exist throughout Nature. Karma is the inerring law which adjusts effect to cause, on the physical, mental and spiritual planes of being. As no cause remains without its due effect from greatest to least, from a cosmic disturbance down to the movement of your hand, and as like produces like, Karma is that unseen and unknown law which adjusts wisely, intelligently and equitably each effect to its cause, tracing the latter back to its producer." - The Key to Theosophy, H. P. Blavatsky
"Do not worry; cultivate the habit of being happy." - Samael Aun Weor