While definitions vary couple-to-couple, there are some common underlying factors, such as secrecy, deception and emotional volatility. However, according to experts speaking to Women’s Health , there are five definitive types of cheating and surprisingly, two of them may not even involve your partner. However obvious it may seem, even physical infidelity is not necessarily immune from ambivalence. Grey areas arise when you get into the minutiae of intimacy, which your teenage self will recall as an all-inclusive scale ranging from kissing to intercourse. Essentially, this boils down to harbouring feelings for someone else which, Barnett explained, is something that really is beyond your partner’s control. However, Mason argues that in order for these feelings to count as infidelity, they need to be acted upon. Yep, hiding your spending habits from your other half can be considered a form of infidelity, Lundquist argues. Typically, this classification arises when such spending affects both people in the relationship and yet one person insists on harbouring their expenditure, be it for personal or professional reasons. According to Dana Weiser, human development professor at Texas Tech University, social media infidelity is also becoming common in romantic partnerships and usually takes two forms.