I am sorry to hear about the passing of your son. Below is a quote I read often after my father passed away, and I hope you also find it comforting. It is from Kahlil Gabran's The Prophet :
When you are sorrowful, look again in your heart,
and you shall see that in truth you are weeping
for that which has been your delight.
Some of you say, "Joy is greater than sorrow"
and others say, "Nay, sorrow is the greater."
But I say unto you, They are inseparable.