Aries and Libra hit it off from the start. But their view of relationships, and approach to the whole romance thing, differs greatly. "Aries is passionate, forthcoming, and they don't like their time wasted [while] Libra is very romantic, likes to be partnered up, and likes to take their time to make a decision," Mckean says. So despite an initial lovely pairing where Libra brings softness and Aries brings passion, things can get tricky down the line.

In some instances, forcing a relationship between these two can end up toxic. Luckily, neither of these signs is particularly prone to holding a grudge.

Taurus and Scorpio can handle each other, that's for sure. But that may not actually be the key to a healthy relationship.

Staying true to each other might actually get the better of this pairing. "As fixed signs, they are both going to be extremely loyal. This is a couple that will likely stay in the relationship long after their expiration date has come up," Mckean says. These two stubborn signs might attempt to keep things going when they shouldn't be, and that can be quite toxic.

Gemini and Sagittarius will definitely have a lot of fun. But beneath that, they might not always develop the level of trust needed to truly feel like they can be their truest selves together.

"This is how the toxicity starts: by not feeling secure enough to be theirselves with each other," Mckean says. Luckily, this toxicity is more on the level of never reaching true comfortability together, rather than anything dangerously volatile. And a breakup between a Gemini and Sagittarius will likely be quite amicable and kind.

At the beginning, Cancer and Capricorn feel like a sure bet. "In many ways, Cancer and Capricorn are perfect for each other. Both are all about tradition. Both like having well-defined roles in a relationship," Mckean says. Unfortunately, both of these signs are both ruled by the Moon, and can (sometimes literally, according to Mckean) change with the phases of the moon as well.

If these changes don't align, things can get toxic — especially because they take relationships seriously and want to stick it through. A relationship past its expiration date, however, is not usually a healthy one.

Aquarius and Leo are fascinated by one another. But when things hit a bump in the road between these two polar opposites, the relationship can get messy.

"It'll be a perfect magical and mighty storm ... but it's ultimately a storm nonetheless," Mckean says, "... If they do break up, it's a done deal. Neither will want to cross paths with the other again." Until then, the two of them desperately clinging to something that's no longer magical can be pretty toxic.

Unlike the other opposing signs, Virgo and Pisces don't necessarily have the magnetic pull of undeniable chemistry. They do, however, still have the tendency to start with a strong connection that might eventually fall apart.

Instead of being drawn in by passion, Virgo and Pisces find refuge in one another. But by desperately clinging to this comfort, they can delve into toxicity. "Both signs aren't prone to want to hurt anyone's feelings, so they both will be ultra-accommodating and avoid trying to break up with the other in order to spare their feelings," Mckean says. In doing this, things can become quite unhealthy. Luckily, these signs aren't prone to holding grudges, and will more likely just put their heads down and move on.

Experiencing the rise (and possible fall) of "opposites attract" magnetism is a natural thing that can happen to anyone, regardless of zodiac sign. But for each sun sign, there is an opposing partner who can bring this out in them. Some of these relationships may end up working out, and some may never really get off the ground, but for all of these pairs, dealing with vastly different personalities will likely be an issue that exists over the entire course of the relationship.