I have been married for one year.
指状态(婚姻关系)至今已有1年
I have married.
指动作,很可能你刚刚和谁结婚了,现在还在蜜月期,兴奋期.
I have been married.
指状态,但时间没有延续到现在,因此为过去一段时间的状态,暗示现在是单身,但结过婚。