Hi, I'm a Virgo with a Libra rising, and I hang out more with Pisces. There's a lot of a history with this sign and there are many others that I know that are Scorpio with a history of friendship and family, too. Earth signs and water signs are polar opposites, though they have a tendency to be with one another even though the elements work differently. It's possible that the two polar signs staying together can be beneficial if one of them is trying to heal themselves, because the opposite sign can reflect (just like other signs, though in its own way) the nature of the discomfort within the person who is trying to heal their life experience.
I have had compatible friendships with Sagittarius individuals, this turned out to be very nice. I find that Gemini, even though the two signs are different, have a way of connecting. There are so many aspects involved, though. It's better to look within your spirit or heart, the same thing, and recognize the previous relationships with those you've known very well to acquaintances through the lessons, experiences that are nice and sometimes odd. This will help learn more about the self, which is a beneficial way to improve relationships with others.