When you know it's not working out, but there is still love, you're torn in between staying and leaving.
"You learn that love doesn't mean leaning, and company doesn't mean security"
Not all houses were built to last. Pain is inevitable and as you take that path down the other road, you feel the crumble of this solid thing that you've built with your whole heart, soul and might. Leaving may have been the last option you'd take but as you walk further, you will find that you could actually keep moving forward.
"You begin to accept you defeat, with your head up and with your eyes open"
As much as there was love in between, if hurting was the most visible trait, then you will find that there's only so much wound a person can take before succumbing to it and watch their soul die.
"After a while, you learn that even sunshine burns, if you get too much"
If you can take the pain that the other person puts on you, you could also take the pain of leaving. It will feel like thorns on your feet. The further you walk, the deeper the cut is but it won't last forever.
"And you learn that you really can endure, that you really are strong, and you really do have worth"
You will find that strength to carry one someday, and you will finally understand why the house you built didn't last.
"And you learn, with every goodbye, you learn"