There have been a lot of studies over how relationships change who we are. Apparently love could alter the way people see themselves. There have been a lot of developments in this study as of late. It is argued that in this world there is nothing more important then finding love. We are all fundamentally alone in this world and if we can find someone who can love us for exactly who we are it distracts us from this truth, maybe even convinces someone otherwise. The first step in finding love is the initial attraction of a potential partner and apparently we will sometimes alter who we are spark a love interest.
In most cases one partner will change traits about themselves to have more in common with the other. In one study there was research conducted over an experiment where real people were exposed to fake dating profiles. The fake dating profiles would have information about them that contradicted what the real people have written about themselves. Over time, if the real person was attracted to the fake profile, they would alter the information about themselves as a way of evolving into a more desirable candidate.
This approach at finding a mate has more to do with the early stages of dating. A lot of the initial attraction has to do with finding shared interests. For example, if one partner likes to listen to Jazz music it seems rather harmless that the other person will suddenly get into jazz too, as a means of breaking the ice. Over time hobbies and interests are more trivial when it comes to a solid relationship, as anyone with long-term relationship experiences probably knows.
These are positive personality traits that are shared and the early studies focused mainly on this, common sense to some people who date regularly perhaps.
One partner finding a new appreciation for wine while the other starts following politics more closely is harmless and perhaps even a good thing. It could help two people grow in a way that they may not have otherwise. The most interesting developments on this research though is the fact that partners are also willing to adapt a persons flaws; things such as forgetfulness, shyness, absent mindedness, etc. Almost any flaw a potential partner was willing to compromise for the exception of very serious negative traits like rudeness and selfishness.
The biggest factor on what determines how willing one partner is willing to change for another has to do with their self esteem. The lower the self esteem, the more willing one is to be molded to make themselves available for any potential mate.
One thing to take from all this is how important love is to all of us, and in way you could draw from this study that is one thing we universally see as greater than ourselves and the prime focus of our desires and goals. It is important though to understand how much a person is changing you and if it is having a negative affect on you. If you have to become a entirely new person to attract someone it probably is not real and has no hope in developing into anything real.