Some of those "Sign Compatibility" lists may indicate that your "opposite" Sign is one of the "difficult" ones for you - for example, Aries with Libra, or Taurus with Scorpio. It would be better to think of your "opposite" Sign as a "complementary opposite", which means the two Signs "complete" each other. What one lacks, the other has. This sometimes creates a mutual admiration - either conscious or subconscious. Two complementary opposites can make a good "team" in business or marriage.
Being opposite, these Signs do have some traits and drives which are almost the exact opposite, but other traits and drives are actually "similar, but different". At the very least, opposing Signs create an interesting and perhaps lively relationship, not one which is just "too comfortable" or boring.
Signs which are opposite are always of the same Quality (both are either Cardinal, Fixed, or Mutable). This means that parts of their nature are similar. Taurus and Scorpio are both "Fixed" Signs, which explains why they are two of the most "stubborn" Signs. Gemini and Sagittarius are both "Mutable" Signs, which explains why they are both "flexible" and "adaptable". Opposite Signs are always in Signs of a different Element (Fire, Earth, Air, or Water), but these will always be Elements which are compatible, such as Earth (Taurus) and Water (Scorpio), or Air (Gemini) and Fire (Sagittarius).
Signs which are opposite, like Taurus with Scorpio, or Leo with Aquarius, often create a physical attraction and add passion to the relationship. (Sometimes it's a bit of a "love/hate" kind of relationship, but not always at that level of intensity.)
The Sign of Aries is opposite the Sign of Libra, but both of these are "Cardinal" signs which are "initiators", meaning they are active, not passive. They can be competitive, assertive, and sometimes even aggressive. Aries is a cardinal FIRE Sign, which makes it truly love a physical challenge, and even a conflict, as something to overcome, "conquer", or win. When you think Aries, think of a centurion in the Roman army. Libra is a cardinal AIR Sign, which makes it love a mental challenge or conflict (but NOT a physical challenge or conflict) as something to overcome or "win". Libra is assertive only in a mental or verbal way, so people with Sun in Libra may like to negotiate, debate, argue, engage in a battle of wits, or go head-to-head in a court of Law. Like Aries, Libra may have a competitive drive to come out the winner; but Libra is also the most diplomatic, fair, and peace-loving Sign. Aries can be a fighter, but Libra hates physical violence in any form.
Both of these "opposing" Signs are opposite in the sense that Aries likes the physical aspects of a challenge, while Libra likes only the mental or verbal kinds of challenges. Where the two Signs are similar is that they do like a challenge and do like to win. You are more likely to see a Libra being a lawyer prosecuting a civil or criminal case in a courtroom; while you are more likely to see an Aries being a policeman combating crime and criminals in the streets. Sometimes you will see a charming and gentle Libra marry a feisty Aries, and sometimes the Libra who does not allow his or her "peaceful" self to express anger will be a subtle "instigator" who provokes the Aries partner to express that anger instead. "Passive-aggressive" is sometimes the Libra style. (The real drive for Libra is to "make peace", not "be at peace". Sometimes, they need to provoke a little conflict to provide the opportunity for some "peace-making".)
Signs That Square Off
Your two most difficult Signs are at a 90-degree angle to your Sign in the horoscope chart (2 Signs between yours & theirs). People born 3 months apart have their Sun in a Sign which is "square" (about 90 degrees) to the other person's Sun Sign; and those born very close to 91 days apart will have the Sun itself square the other person's Sun, which means a stronger challenge! (Moon square Sun is also difficult.) Example: Aries is square to Cancer and Capricorn; while Taurus is square to Leo and Aquarius. Signs which are square to your own Sun Sign have very "different" ways, and will "push your buttons" and trigger some "ego conflicts". These pairs of Signs are so different that they just don't understand where the other is coming from. The Sun Signs that are square to yours include the people most likely to annoy or "bug" you in some way.
There are many differences to make things "interesting", but very few similarities to make things "comfortable". Signs that are square to each other are probably the most difficult combination of all. See how many of your close friends have Sun Signs which are square to yours. Unless you have your own Moon in one of those two Signs, you are not likely to have many close friends in those Signs.
Sometimes these differences can at first create a sexual attraction between people of the preferred genders, but attraction can turn to reaction with annoyance sooner or later. With the non-preferred gender, it is more likely an almost instant annoyance, dislike, or competitiveness.
These two Sun Signs may not show up in your best "love match" list - but IF many other connections in your individual horoscope charts create more harmony, they can STILL be a great match! See
Love Match List