NEW YORK (NYTIMES) - Imagine you are at a restaurant one night and, after dinner, you decide to order not one but two slices of cheesecake for dessert.

Many would say that is unhealthy - or at least indulgent - but everyone deserves a treat once in a while. Right?

If you keep ordering two slices of cake for dessert every night for months, however, your health may suffer.

This is one analogy that Dr Chitra Raghavan, a professor of psychology at John Jay College of Criminal Justice, used to explain how romantic behaviours can transform into a manipulative dating practice known as "love bombing": lavishing a new romantic partner with grand gestures and constant contact in order to gain an upper hand in the relationship.

"One partner, typically male but not exclusively, showers the other person with attention, affection, compliments, flattery, and essentially creates this context where she feels like she's met her soul mate and it's effortless," Dr Raghavan said. "The reality is, the person who is doing the love bombing is creating or manipulating the environment to look like he or she is the perfect mate."

Sounds familiar? Here are some signs and patterns to keep in mind to avoid getting love bombed - and advice for what to do if you think it may be happening to you.

Excessive attention and flattery

One of the complicated things about dating, Dr Raghavan said, is that everything that happens in healthy relationships can also happen in unhealthy relationships. Showing excessive attention is an example.

"If someone pays you attention and is generally present during the first date, that generally signals interest," said Dr Raghavan, who also specialises in domestic violence and sex trafficking. "But there's also someone that pays you interest in such a way that you're consumed by it."

She added that it can be difficult to recognise the mismatch of familiarity (remember, this is someone you have only just met) and affection in the moment, especially when a person is uttering words you have longed to hear: "You are my soul mate", "I never met anyone I feel so close to" or "Everything about you is what I wanted".

"It's very exaggerated, histrionic, but could also be seen as deeply seductive and romantic, depending on what happens in between, what happens after," she added.

Isolation from friends and family

It may seem sweet that your new mate wants to spend all of his or her time with you. But more often, it is a red flag. The person may be a narcissist trying to isolate you from the other connections in your life as a way of exerting control.

Dr Amy Brunell, a psychology professor at Ohio State University, whose research is focused on narcissism in social and romantic relationships, said that while there is not a lot of research on intimate partner abuse and narcissism, there is a connection. Controlling a person's social life from the get-go may leave the person with nowhere to turn when a relationship sours.

"It does plant the seeds for intimate partner violence because, typically, a person will finally have enough and want to get out of it, and then it's really hard," Dr Brunell said.

Over-the-top gifts

Dr Raghavan said that showering new partners with presents is a common way for love bombers to exert influence, and even if they do not have money, they may act as if they do.

"It's part of the idea of excess and overwhelming the person so that he or she is swept off his or her feet," she said, adding that the "constant attention, flattery, seduction and gifts" make it hard "to process that you're overwhelmed. And when you're overwhelmed, you don't see danger".

Narcissists tend to be materialistic themselves, Dr Brunell said, so they may also give gifts to boost their value and self-esteem.

"It kind of reminds me a little bit of the Christian Grey stuff in that series, the chronic high-end gift-giving," she said, referring to the titular character in the best-selling Fifty Shades romance trilogy. Because such characters abound in romantic media, she added, their behaviour "becomes our equivalent idea of romance".

Dr Paul Eastwick, a psychology professor at the University of California, Davis, whose research examines how people initiate and commit to romantic relationships, noted that not all grand gestures should be red flags.

"Generally speaking, the way we give affection to other people, the way we show them that we care about them, the way we try to support them - all of those things tend to robustly predict good outcomes," he said.

Love bombing, he said, likely represents a "small subset" of that behaviour.

Post-love bombed

In healthy adult romantic relationships, support, desire and affection tend to be reciprocal, Dr Eastwick said. But in cases of love bombing, attention flows in a single direction: One person tries to become the other's whole world.

Dr Raghavan said that people who have been love bombed often feel as though they have lost their sense of self, which can take a long time to rebuild.

"You lose the sense of who you are because little things are being managed for you and these little things can be anything from how you dress to how you present yourself," Dr Raghavan said. "But it can also be the kind of jokes you're allowed to tell in public or the kind of woman that he wants you to be."

These experts said that victims should be patient with and forgive themselves, and could also benefit from therapy. They should try to reconnect with the activities and people who mattered to them before the love bomber entered their life, the experts added.

"That needs to happen, the acceptance of the tragic events and embracing the positiveness of the future," Dr Raghavan said.