两肋插刀 meaning in English

help (one's friend) at the loss of one's life

Bob ' s like a blood brother and would do anything for me
鲍勃象亲兄弟，愿意为我两肋插刀。
Kelly : anything for my best pal
凯莉：愿为朋友两肋插刀。
You kept your head on a swivel
你们为兄弟两肋插刀
I can ' t trust you . you can ' t trust me . i ' m not taking a bullet for you
我不信你，你也别信我我不会替你两肋插刀
We bent over backwards to help him , and he never even thanked us
（我们为了帮他简直是两肋插刀，可是他连谢都没谢我们一下。）