The key is simple: make your decision ahead if time.
Sounds impossible. How can I know how to decide before I know what is asked? Life is full of opportunities for bad decisions. You can be sure that the devil will send to you the wrong woman or the wrong man to marry. Make up your mind ahead of time that you are not going to be fooled. A potential spouse must meet some standards. Put it down on paper. Remember love can be ginned up falsely (called lust) or whatever. The person who thinks through a major decision will end up with a better outcome.
Make up your mind that you won’t compromise with evil before the opportunity comes to you. I was offered a pile of money and endorsements when I ran for the Legislature. I sad “no.” I was nice about it. The offer was generous. This group expected me to follow their corrupt, immoral doctrines when I was in the Legislature. I said no ahead of time. I did not win the election but I was nobody’s “yes” woman either. The only lobby you have to answer to is the God Lobby; God is more than competent to tell you how to vote.