I think this song is talking about, a loyal friend. Who is always(I'm the rock) (I'll designate myself) there for her friend, and is always ready to give this friend comfort when the person is going through pain. She’s her friend’s shoulder to cry on EVEN when this person get’s a broken heart (It's OK , Love is only meant for some), "EVEN" because while she’s giving comfort to this person, she’s actually giving comfort to herself, because she obviously feels more than friendship for this person, who doesn’t even take note of it( I'll play it straight, While you laugh and drink and party all night long...)
I think this song is talking about, a loyal friend. Who is always(I'm the rock) (I'll designate myself) there for her friend, and is always ready to give this friend comfort when the person is going through pain. She’s her friend’s shoulder to cry on EVEN when this person get’s a broken heart (It's OK , Love is only meant for some), "EVEN" because while she’s giving comfort to this person, she’s actually giving comfort to herself, because she obviously feels more than friendship for this person, who doesn’t even take note of it( I'll play it straight, While you laugh and drink and party all night long...)