It varies from family to family.
Mrs Thomas was the mother of Dean Thomas. Though she was a Muggle, her first husband was a wizard, but he never told her so, believing that not knowing the truth would keep her safe. He deserted Mrs Thomas when their son was still a small boy and was eventually murdered by Death Eaters.
Mrs Thomas remarried a Muggle man and had several children with him. The family lived in London and were described as having "a very happy home life".
When a letter arrived for Dean from Hogwarts in 1991, Mrs Thomas considered the possibility that her first husband might have been a wizard, but, like her son, was never able to confirm this suspicion.
Seamus Finnigan (b. 1979/1980) was an Irish half-blood wizard, son of Muggle Mr Finnigan and Irish witch Mrs Finnigan. Mr Finnigan did not learn this until after they were married and it gave him a "nasty shock" when he first learned it.
Tobias Snape married the pure-blood witch Eileen Prince. He abused her mentally and emotionally, as Harry Potter saw in Severus Snape's memories during an Occlumency lesson. It could be surmised that he was physically abusive as well. Why they began a relationship and got married is currently unknown. Eileen may not have told him about the wizarding world before their wedding.
Merope developed an obsessive love for Tom Riddle, a handsome and wealthy Muggle. After both her father and brother were imprisoned in Azkaban, she bewitched and married Tom, getting pregnant. A year into their marriage, Tom Riddle was liberated from the effects of her magic and fled. Merope ended up alone in London and later died at Wool's Orphanage, soon after giving birth to her son whom she named Tom Marvolo Riddle.
Most of the families ended with a bad ending because of either societal pressure or some other problems. But I am yet to see a family with a muggle member who was accepted wholeheartedly and where they could raise their kid like in any other magical household. It can't be totally ruled out though.