The mind governed by the flesh is death, but the mind governed by the Spirit is life and peace. ~ Romans 8:6
God makes a steady point in scripture, directing us to get our minds right. No matter if you see the glass as half empty or half full... the point is to remember that it's God's spirit which should fill our cup.
When we get that right, we find peace and a pretty cool life.
So, get a grip on your thoughts and fill your cup with His spirit. Look for God in the world and you'll find Him. Everywhere and in every situation.
Can you see your cup? Regardless of whether it's half full or half empty - is it at least filled with Christ's love?