Mismatched couples get together all of the time. While it may seem to work at first, relationship compatibility matters a lot and can cause serious problems down the line.  

Measures of compatibility vary, and some of them are harder than others to notice. However, even if a couple doesn’t realize they’re incompatible at the start, they begin to realize once they are falling out of love.

Commonly, people fall in love and ignore these signs of incompatibility even though they may be visible early in the relationship.

Many years may go by before the extent of the mismatch is recognized. Oftentimes, people don’t realize they aren’t right for each other well into married life. And, it’s this realization that causes all sorts of relationship problems. So, which relationship compatibility factors matter? 

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Here are 3 tiny compatibility factors you need for a relationship that lasts:

1. Personality types

Compatible personality types are generally essential for an intimate relationship to develop.

Aggressive people have difficulty living with passive mates without conflicts occurring. Once the bloom of love has diminished, aggressive spouses may become aggravated by the quieter, passive, and often shy or dependent partner. More likely, boredom develops.

Often, the passive or dependent person wants more tenderness and warmth, especially in the bedroom, than is offered by a more aggressive partner. Marked differences in personality types will often create relationship problems.

An introverted and inhibited person clashes with a suspicious and angry spouse. A fearful and phobic partner has trouble with an outgoing and fearless mate. One who is afraid of getting close to people may be in conflict with a person who reaches out and befriends everyone.

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2. Intelligence

Levels of intelligence can negatively impact a relationship when the woman is decidedly more intelligent than her partner. Some couples can survive this, but eventually, the woman outshines her partner in work, play, and their interactions.

The various positive elements in the relationship often compensate for this difference and thus relegate intelligence to a low level of influence.

Many couples can handle a relationship when the woman is less intelligent. However, it often backfires when the difference is too great and the woman cannot communicate.

The way a person uses intelligence is often more consequential than the actual intelligence levels, especially if they’re making their partner feel bad. The freedom to express warmth, love, and deep caring influences a couple far more than knowledge of current events.

Reaching deeply into a person’s feelings and sharing intimate and meaningful discussions markedly affects the viability of a loving relationship. Sensitivity, empathy, and intuition are powerful forces for true relationship compatibility.

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3. Education

With the large number of women (half of all college students) seeking graduate and post-graduate education, the marked differences in this area have diminished. If this causes communication and relationship problems, it’s difficult to say.

Advanced education usually determines knowledge and expertise in certain categories. A PhD in chemistry, physics, anthropology, and other subjects does not fully indicate a person’s intelligence. Being self-educated and a dedicated reader can help many people become highly educated, often more than those with advanced degrees.

At times, problems arise when a highly educated person marries a relatively poorly educated person. Their ease of communication may suffer, jeopardizing the intimacy and shared pleasure of conversation. By pursuing education and learning life-long, problems in this area will tend to be minimal.

Incompatibility in relationships occurs in many guises and needs to be recognized early before relationship problems arise.

However, there are many ways to fix relationship incompatibility issues like personality modification and psychotherapy. Improving education can reduce feelings of inferiority and enhance communication skills.

Intelligence can be modified by increasing creativity and developing areas that interest you. As self-esteem rises, a greater desire to improve oneself develops and this can become a winning combination for self-development.

Reaching the highest levels of love, intimacy, communication, and sharing comes from building understanding and trust. Relationship compatibility matters, but there are always workarounds when you feel yourself falling out of love.

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Marvin Berenson, M.D. is a Clinical Professor Emeritus of Psychiatry, a psychiatrist, lecturer, and author.