The ring is on your finger. The date has been set. You're determined to be a vision in white... until you spot a red flag. You want to say "I do," but all signs point to "I don't." Regardless of how deep into the wedding plans you are, there are just some dealbreakers that can't be overlooked. While the notion of cancelling the big day may seem too painful entertain, it likely will save you a lot of headache and heartache in the long run. Here are a few really good reasons not to move forward with the big day. Cheating: once a cheater, always a cheater. Whether it's a long-running affair or a bachelor party boo-boo, finding out your spouse to be has been straying is definitely a reason to pull out of the wedding. Once the damage is done, you will likely never be able to trust your mate again. And trust is the foundation of any solid relationship. Having misgivings about your choice of flowers or wedding favors is one thing.