Advice for one of the most screwed up situations....?

I'm "engaged" to a man that's legally separated. Four years of going through a divorce and he's not legally divorced. We're in the middle of me adopting his son. We're also in the middle of purchasing a home (together) across country. Tonight I'm weeding through some paperwork, tossing out what's trash, packing what we need to keep. I came across a life insurance policy that was taken out about a year ago and his "ex" wife is the beneficiary. In all fairness to him, he couldn't find her for the divorce signatures and that's what took so long for the divorce. His company requires her to sign off as beneficiary because they're still married so he didn't bother asking her. He says he knew she wouldn't sign anyway. They were only married a bit over a year. Meanwhile, he questioned me as to why I put my sister down as my beneficiary on some paperwork last week. My reply: he's still legally married!!! Wouldn't this implicate his estranged wife with MY insurance policy? Am I wrong for feeling uneasy about this whole picture? Why do we allow men to put us through this crap?