I'm going to explain this song in my perpetive of the song it could be varied as I link it to my past experiences also.Im going to explain it line my line. Two people will of course have experiences im the past where a previous lover have broken their heart or hurt them.Shes now met a new person that's has a broken heart and she's say how "broken hearts are made for two" they can now be united and make one whole heart which is new and working again.She says she should even really be trying to get to know someone new or get anybody to love her again because she might mess up everything.Even though she knows she's hurt about other things and know she shouldn't be trying to love someone else she's going to do it anyways and is going to make this her favourite mistake.Shes crazy and hard to handle so if he decides to stay with her it's on him but she's warning him about it."Your so brave stone cold crazy for loving me" She's saying like wow all the downfalls about me you still want to get to know she's surprised as nobody really wants to really love her.Jhenè then mentions how if her lover wants to mess about and just use her then he should just leave and now even continue anything as she's had "scars on her heart" as in she's been hurt by previous lovers and she feels like there's no hope left but if he's ready to commit than it's fine by her because she'll be ready to love him.She then repeats the your so brave.The last line "I hope yu make it out alive" she knows she's hard to deal with and has all these trust issues because of what had happened to her but because he said he was willing to go through the battle of her she wishes him the best luck.