My mother married my abusive father (who cheated on her blatantly) because she discovered she was pregnant and felt she had no choice. They didn't love one another at all. They thought they were doing the right thing. My biological dad was not a believer. My mom was a believer, but she had been hurt deeply by some in the church and left for a time...and ended up in a mess. They divorced when I was two. I never met my father, but I did find his family when I was adult, and I know that he knew the Truth before he died.
My mom remarried and I was adopted and raised by my stepfather, who was the most amazing man I've ever known. My stepfather was not a believer until shortly before he died and there were times when my mom wrestled with her faith because she was torn between things she knew she should not do/places she should not go and things he wanted her to do. Eventually she realized it was tearing her apart and leading to serious bouts with depression. She got back in the Word, drew a line and insisted that she attend church regularly, tithe, etc. Eventually he got the message, understood the amazing things God did in BOTH of their lives because of her walk with Christ, and he accepted the Lord before he passed.
Lessons:
Don't marry for the wrong reasons
Don't marry unbelievers
Don't allow anyone or anything to cause you to walk away from Christ, even other christians or family members
Don't date unbelievers who can persuade you to do things you know are wrong
Understand that your actions within your marriage don't just affect you, they affect your children and extended family as well.
If you ARE married to an unbeliever when you come to Christ, all is not lost. You can be a faithful witness to lead them to the knowledge of Christ.
You CAN begin your life again if you are in an abusive relationship
If you are unmarried with a child, there are wonderful people out there God can lead you to who will help you build a home and raise your child.
I loved my parents, even my biological father I never knew. I do not write this to villify them, but to honor them. They would all want someone else to benefit from their mistakes. They fell down..hard...but they completed the race in the end. They taught me that when I make a mistake, I should at least try and learn from it so as not to repeat it.