why is everything with you so complicated 正确
疑问句的be动词或助动词要提前.
只有当陈述句的时候,句子才是陈述语气,比如why everything with you is so complicated 如果是用陈述语气,那么这个句子一定是作为从句,前面有主句：比如
They ask why everything with you is so complicated
is的位置在疑问句中就是在主语的前面,比如上面的you做主语,放在you前面,如果是thing,就是thing前面,这里是everything就在everything前面
供参考