Let's say you caught your partner in an affair or they worked up the guts to tell you the truth and let you figure it out from there. (Kudos to them, but still.) Either way, cheating is cheating [1], and it definitely doesn't feel good to be in the position where your partner betrays your trust and looks elsewhere [2]. The question then is: do you take them back? Is forgiveness an option? To decide, it's worth looking into the idea of a "cheater," and whether or not a cheater is always a cheater [3] and will repeat the behavior without learning from past mistakes. Here's what to know before immediately accepting an apology and continuing on in the relationship.

What Makes a Cheater a Cheater?

There's no definitive answer, as reasons can vary based on the individual and situation. "Research shows that people cheat for a variety of reasons, so it's difficult to pinpoint certain characteristics of all cheaters," David Bennett, a relationship counselor and owner of Double Trust Dating and Relationships [4], told POPSUGAR. "For example, some people cheat for sexual variety, while others do situationally (such as when intoxicated)," he says. Some may even cheat when a spouse is sick [5] while trying to move on with life and be a better partner when they can at home.

Hormones can play a role, too. "Another indicator of likelihood of cheating is higher testosterone [6]," says Bennett. "So if your partner is more traditionally masculine or has other signs of higher testosterone (such as being in a leadership position), the odds of them being a cheater are increased," he says.

Will a Cheater Always Cheat?

Unfortunately, "Multiple studies have shown that the most reliable quality that indicates a person will cheat [7] is that he or she has cheated in the past," he says. "So, if you know your partner has a history of cheating, I would consider that a good predictor of future behavior," he says.

Yet, situation plays a role, too. "It is possible a cheater may get his or her needs met in the area that led to the cheating, and therefore stop cheating," he says. Or, perhaps the partner they're dating is actually what they're looking for and different from previous relationship. "If your partner has cheated in the past because of attraction issues, then if you're more physically attractive to them, I would say that could lessen their desire to cheat. The same is true if you're emotionally available and your partner cheated in the past because their previous partner was cold and distant," he says.

The problem with this line of thinking, however, is that cheating isn't the fault of the person being cheated on. Even if their previous partners "drove" them to cheat, the person who cheated in the past still made the decision to cheat rather than end the relationship first.

What's more, some motivations for cheating may be difficult to completely eliminate, such as a mere interest in others or the need for new sexual partners. "For example, many people cheat because they want sexual variety, and by its very nature, monogamy will limit this," he says.

On the flip side, it comes from weakness, where others cheat at moments they don't feel loved, he says. "Again, it's unrealistic to expect someone to always feel loved every minute of a relationship. So, while situation does matter, most people will find it hard to avoid all the situations that led to them cheating previously," he explains.

The Takeaway?

Proceed with caution. "I would be very careful getting with someone who has a history of cheating. Research shows people cheat for a variety of reasons and in a lot of different scenarios. Trying to figure out why your partner cheated in the past and working to avoid every possible trigger for them in the future seems like a lot of work, especially since the research is clear that cheaters tend to do it again," he says. If you decide to date a past cheater, be careful, and keep your guard up.