I don't believe it for a moment and it's that belief that causes so much unhappiness and struggle for people. It's completely unrealistic and comes from a fairy take which isn't real life to begin with.
Any marriage or relationship cycles through high and low periods. That's real life. And it's how we handle the low cyles that determine how the relationship is going to work. The same applies for us when we're single.
They're like anything else in life. They cycle up and down. I've been married for 26 years and have seen and been through these cycles. I'm not saying marriage is bad. I'm just saying it's not perfect.
I do believe in happily married ever after because what we believe in we could make it happen.....may be at first you might fail but keep trying and evolve in the process.
I am happily married. I have been for 14+ years now. I believe there is nothing impossible for God, including happily ever after.
I'm a lot happier single (after having been married twice).