There’s a fine line between a close, platonic friendship and a full-blown emotional affair. If you’re in a relationship (and want to stay that way), be very careful not to cross it.

Below, marriage experts share seven signs you may be on the verge of emotional infidelity.

1. You complain about your spouse to others.

Everyone complains about their spouse to friends or co-workers here and there. But ranting to others could be problematic, especially if you’re divulging your feelings to someone you’re potentially interested in, said Aaron Anderson, a marriage and family therapist in Denver, Colorado.

“Instead of talking about it with their partner, many people will bite their lip and push the problem underground ― or tell the other person,” Anderson said. “If the marriage problem is something you feel strongly about, it usually comes to the surface, and it sometimes leads to an emotional affair.”

Instead of ranting to this totally-platonic-not-at-all-romantic-interest third party, tell your spouse directly.

“You never know, you might even become closer after talking about it with each other,” Anderson said.

2. You think about the other person when they aren’t around.

If your thoughts are preoccupied with a friend and some alternate life you could be living together, you’re likely doing damage to your primary relationship, said MarieLand, a psychologist in Washington, D.C.

“If the right circumstances exist, emotional infidelity is all too common and convenient,” she said. “There’s nothing terrible about enjoying a little attention from time to time. But when you’re spending time with your partner and stillthinking about the other person, you may be crossing the line into emotional cheating.”

3. You start to hide things, keep secrets or outright lie.

Even if it’s a lie of omission, it’s a serious red flag when you purposely avoid telling your spouse about the other person, said Marni Feuerman, a marriage and family therapist in Boca Raton, Florida.

“Ask yourself: Would I be in the clear if my spouse overheard a conversation between me and this particular friend?” she said. “This should help you figure out for sure if things may be headed in a troubling direction.”

4. You compare your partner to the other woman or man.

“If only my girlfriend was more like Jennifer at work” can quickly escalate to “I wish my girlfriend was Jennifer at work.” What’s more, you probably aren’t being fair to your partner when you compare her to a work crush, Land said.

“Maybe you’re raving about how funny your coworker is, but keep in mind that you two aren’t trying to make a relationship work. You aren’t sharing the demands of house chores and demanding schedules,” she said. “Give your real partner credit for what they’re doing right and recognize that you may be giving the other person too much credit.”

5. You think about the other person during sex.

It’s an obvious red flag if you’re comparing your partner to the other person in bed. You may figure your fantasies are keeping things hot between the sheets, but in the long run, it’s a risky gamble, said Diane Spear, a therapist in New York City.

“It can actually take your sexual energy out of the relationship,” she said. “Put it this way: Would you want your partner to think of someone else while having sex with you?”

6. You’d rather be anywhere else than home.

Even if there isn’t another person, it should be of concern if you’re actively avoiding going home to your spouse, Anderson said.

“When you don’t want to go home, it’s generally because something else is compelling outside the relationship. And if it’s more satisfying to you than going home, there’s usually some kind of emotional reward you’re getting out of it,” he said. “It’s a slippery slope.”

7. You’re doing something that would bother you if your partner did it.

The ultimate litmus test for whether you’re emotionally cheating is pretty simple: If your spouse was behaving the same way, would it bother you? If the answer is “yes,” you may be on verge of an emotional affair, Spear said.

“That’s a sign you’re in a gray zone,” she said. “You’re crossing over, whether it’s meeting someone or putting way too much thought into someone else.”