Pinterest and Tumblr are overflowing with images proclaiming that you should accept people how they are or start living without them, approximately one million Marilyn Monroe quotes about handling someone at their worst, and general twenty-something angst about our inability to change less-than-desirable personality traits.
Perhaps it's true that you cannot force someone to change (and that would hardly be a healthy relationship). However, recent personality psychology research suggests that people can and do change significantly, and that key people in their life can be the catalyst.
Several research studies over the past few years have shown that your personality changes over the course of adulthood, specifically as a result of life events such as entering into a relationship or career advances. From age 20-65 an increase in positive traits (think emotional stability and responsibility) is reported, and titled the Maturity Principle by psychologists.
Well, duh. I think any girl who has dated both men her age and older men can vouch for the validity of these findings. Growing up comes with a lot of unfortunate consequences (hi there, taxes) but a lot of great ones too.
The part that stuck out to me is that happy people had a greater increase in the positive personality traits over the next four years compared to their unhappy peers. So on the rough days, remember that a positive outlook doesn't just help you today, but maybe for years to come. While you're at it, smile at as many people as possible - you never know what kind of change you could cause.