Can we be Happy all the Time?

Surely God feels sorrow: (check scripture) http://www.smpt.org/docs/england_element1-1.html

So just as God feels sorrow, he also feels happiness. God is perfect, so his happiness comes through our progression and happiness, and vice versa.
As we become more like him, we expand our happiness through our families as well. As we are sealed to Him in the temple with our families, we eternally become linked together in an awesome family tree. Every evil man has his end. Every righteous man has his eternal growth. So by our expanding happiness, and his righteous family growing, he and we have an eternal happiness that is always growing.
But what about Godly pain?

The following passage is from the awesome short read "The Screwtape Letters". Its a letter from a teacher Demon/Devil to another student devil who has been trying to tempt someone. That person died, and went to heaven. Look at this interesting idea:

"Pains he may still have to encounter, but they embrace those pains.  They would not barter them for any earthly pleasure.  All the delights of sense or heart or intellect with which you could once have tempted, even the delights of virtue itself, now seem to him in comparison but as the half-nauseous attractions of a raddled harlot would seem to a man who hears that his true beloved whom he has loved all his life and whom he had believed to be dead is alive and even now at his door.  He is caught up in to that world where pain and pleasure take on transfinite values and where all our arithmetic is dismayed." (Clyde S. Kilby, The Screwtape Letters, 93)

So God can feel sorrow, but those pains are full of charity, even the purest of love and righteousness. So even those pains we would easily trade for the greatest of pleasures we can get on this Earth. Thats an amazing thought.