A/N: House's POV
I don't believe that happy endings exist without pain. I believe there are victorious endings and endings where one comes out on the other side either unscathed or as damaged as could be (but feeling like it's the best day they've lived), but happy endings are the end blocks of fairy tales.
For there to be a happy ending, there is the unspoken rule that first one must undergo a series of challenging and more often than not, unfortunate events. Pain. Suffering. They are both requirements of arriving at a final point. No one can escape them.
Life is pain. Life is facing that pain head on and passing the time until the day Death arrives. Life is a puzzle consisting of pain and every other emotion imaginable. Life sucks.
There lies the proof that there is no such thing as a happy ending without pain.
One cannot ever be truly happy if they have lived through bad circumstances because as things go, these memories will surface one day and remind their beholder that happiness is merely an illusion that will slip through their fingers like water, cling on only for the shortest of moments before fleeing.
For there to be happiness at the end of the metaphoric tunnel, there is a price to pay in misery.