Getting tired of the same issues that plague your relationship? Are you stuck in a pattern over the same fights? Its likely not because you "married the wrong person" but more than likely a cause of expectations based on how you were parented which result in core patterns of relating. These core pattern issues are what therapists call "Attachment issues" as they are based on the attachments you came to expect - or not - as a child. Children can have secure, anxious or avoidant attachment styles.
Growing up in a volatile home and needing to be more independent in handling your emotions on your own because parents were too busy fighting would then cause an individual to maintain that independence into their marriage - mixed with a person that grew up with a lot of attention from both parents and....BAM...the more needy partner ends up with an emotional crisis around needing to feel more securely attached and the partner is unable to respond to the need due to the pre-existing avoidant pattern.
This is just one example among many that can get couples into trouble and having spouses thinking they've married the wrong person when the reality is it's a behavior pattern that needs to adapt to a new relationship. This can take a lot of difficult emotional work for a period of time, but once couples reach the other side there is a deeper intimacy and a more whole-person understanding between the spouses.
There are 5 different love style that can interact: The Avoider, The Pleaser, The Vacillator, The Victim and Controller love styles (also known as the Chaotic love style). These styles can pair-up and initially the opposite qualities attract and then they can attack. Not feeling attached to your partner is one of the most emotionally dis-regulating feelings for a person. You'll see the dis-regulation in children when they lose their parent at a store, or feel unsure of a parents' love. These behavior patterns repeat into adulthood though the dis-regulation can show up differently. Some adults to continue to throw tantrums and some hide in their work, or spend their time with the children leaving the marriage to suffer.
The good news is that with professional help the couple can start to recognize their core patterns and in the safety of a therapeutic situation can start to rebuild, the often unknown, broken emotional attachments. The couple then internalizes the therapeutic techniques and are able to "catch" their pattern and stop it before it gets out-of-hand.
Thus, it is not the wrong person you've married but just the wrong understanding of how they receive the way you grew up loving your birth family. The patterns of your biological family usually do not work within the structure of your newly created family - with the person you married. This is also works for Blended Families and in the relationship patterns between blended family step-kids to the new stepparent. Figuring out what's happening for another person emotionally, will allow the patterns to be side-stepped to create a more peaceful home and a new securely attached relationships.
For more in-depth information on this subject or to discover your love style I recommend the book How We Love by Milan & Kay Yerkovich.