You are a little soul carrying about a corpse, as Epictetus used to say.

If you are distressed by anything external, the pain is not due to the thing itself, but to your estimate of it; and this you have the power to revoke at any moment.

Such as are your habitual thoughts, such also will be the character of your mind; for the soul is dyed by the thoughts

Shame on the soul, to falter on the road of life while the body yet endures

You have power over your mind - not outside events. Realize this, and you will find strength.

To live happily is an inward power of the soul.