1. He Gets Weird when You Mention Her

If he acts weird whenever she enters the room, or when you simply mention her name, then something fishy is going on. There's no reason for him to act out of the ordinary when she's brought up. If she's the only one he acts bizarre around, and he doesn't have any excuse for his behavior, then you should be concerned. He might be cheating with her, especially if she's acting as strange as he is. When a partner starts displaying defensive reactions or sudden anxiety at the sound of someone's name, it often indicates hidden guilt or an emotional connection he is trying to hide from you.

2. They Claim to Hate Each Other

If he doesn't want you to figure out that he's been cheating with a certain girl, he might go overboard when talking about how much he can't stand her. He thinks that bashing her will stop you from thinking that he's interested in her. This classic psychological cover-up, often discussed in Psychology Today, is designed to throw you off the scent by creating a false narrative of mutual dislike.

3. He Won’t Let You See Her Text Messages

There's nothing wrong with him having a female friend. However, if he keeps his phone out of your view whenever he texts her, and leaves the room whenever he's on the phone with her, he's acting sketchy. He shouldn't have anything to hide from you, especially when it involves another woman. So be careful. If this digital secrecy leads to him habitually deleting messages, it becomes a major red flag that warrants a serious conversation about transparency.

4. He’s Always Snap Chatting Her

Some people use Snapchat innocently, but a lot of people use it to send sexual photographs. If a certain woman's name is always popping up on his phone, and he'll never let you see what she sends him, then something is definitely wrong. Chances are that she's snapping him the types of photos that you would hate to see. When app usage turns secret, it shifts from normal social networking into potential infidelity.

5. She Always Asks about Him

If you're friends with the girl you think he's cheating with, it's just as important to pay attention to her behavior as it is to pay attention to his. If she's always asking you questions about how your relationship is going, she might be hoping that there's an issue that causes you two to break up. Her unusual curiosity about your private arguments or relationship milestones can reveal her underlying interest in taking your place.

6. He Tells You to Be More like Her

Your boyfriend shouldn't tell you what to wear or how to act. Even more importantly, he shouldn't compare you to any other women. If he's always comparing you to a certain girl in his life, then it means he wishes you were more like her. Even if he isn't cheating with her, he might as well be, because he's still being disrespectful to you. You shouldn't have to put up with that type of treatment. According to relationship guidance from The Gottman Institute, healthy partners build you up rather than using comparisons to undermine your confidence.

7. He’s Always Staring at Her

It's normal for men to look at pretty ladies when they pass by. However, he shouldn't be staring at anyone. If he's always gawking at a certain girl, then he might be cheating with her. Even if he isn't, it's clear that he finds her attractive. When his attention remains fixed on her even when you are present, it shows a clear lack of respect for your feelings and boundaries.

8. He Gets Defensive about Her

It's one thing if they're friends and he defends her, but if you judge her to see how he'll react and he flies off the handle in her defense, he's probably got feelings for her. And he'll get even more defensive if you accuse him of that. If your simple questions lead to anger or accusations that you are being overly paranoid, he may be using defensiveness as a shield to hide his true actions.

9. He Deletes Texts

If you know they talk frequently then all of a sudden the texts stop showing up, he's probably deleting them which screams out guilty because if has to hide them they're probably talking in a way they shouldn't be. When someone goes out of their way to wipe message histories while maintaining frequent contact, it points directly toward suspicious behavior and broken trust in a relationship.

10. He'd Rather Spend Time with Her

This is probably the most obvious on the list, but if he'd rather hang out with his friends and she "happens to always be there" then there's probably a strong likelihood they're cheating. He needs guy time but not with other girls around every time, or he should at least invite you with if he knows she's going to be there. When spending time with her takes priority over quality time with you, it is time to address these major signs of cheating head-on.

If you think he's cheating, sit him down and ask him about it. If you find out that you've been right all along, then make sure you end it with him, because he doesn't deserve another chance. Do you have a sneaking suspicion that your boyfriend is cheating on you? Here are steps to handle the situation constructively: