We’ve all done it-- made promises to our partner only to later break them. New research confirms that those who care the most about the feelings of their partner may set themselves up for failure by over-promising. In contrast, people who are less focused on their partner's feelings and instead more focused on controlling their own behavior promise less but are more likely to keep their word.
Peetz, J., & Kammrath, L. (2011). Only because I love you: Why people make and why they break promises in romantic relationships. Journal of Personality and Social Psychology, 100, 887-904. doi: 10.1037/a0021857