After listening to this a gajillion times and thinking about the title, I've imagined this song to be how someone feels protecting someone else. Like, taking the blame for them, making up for their slack by doing extra work, just being merciful by taking on burdens for them because they're weaker than you. But it's exhausting and painful to constantly lend your strength to someone else, and it takes its toll, even if you're strong. This song is how that feels.
I know my imagined situation doesn't help you at all in the technical aspect of making songs, sorry >.< But I really like how it sounds, especially that electric guitar (I think that's what it is). And the "heavy" sounds like the drums and guitar, mix great with the lighter piano. The piano makes the overall tone feel less harsh, being the one of the few "light" sounds.
...I really know nothing about music >.< So in short, I think this is a great song!