Sagittarius and Taurus! Ugh?

okay. So I've dated many sagittarius in the past. I just have a natural attraction to them. Well, I have this book of relationships that matched you with the exact week of the other person. Well this guy was born three days before the cut off. His match and mine is worst at marriage, but 3 days later and it's be BEST at marriage. I know this sounds silly. But I can't help it. I just keep worrying because SERIOUSLY this book is never wrong. It's proven it's self time and time again. Can someone please give me a peace of mind? Or if your a taurus who is/was dating a sag give both of your exact birthdays? Thank you.