It's true that some couples who starred on TLC's hit series 90 Day Fiancé managed to stand the test of time, but, all too often, the romantic flames kindled after an online fling sputtered out quickly after reality set in.

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Long-distance partners featured on the show will often exaggerate and aggrandize their wealth, living situations, or looks, while others will feign affection in search of material gain. The red flags raised by romantic partners are typically pretty obvious, but, for one reason or another, 90 Day Fiancé stars are willing to overlook them in order to fulfill their fantasies or accomplish their ulterior goals.

Colt Lived With His Mother At 33

Colt and Larissa posing together in TLC's 90 Day Fiancé.

While independence from one's parents isn't necessarily required in a relationship, the fact that Colt could never get out from under the thumb of his mother should have raised a major red flag for Larissa. In a way, it was a side effect of his apathetic approach to life, something Larissa was clearly never content with.

Beyond that, Colt was far too eager to commit to Larissa, asking for her hand in marriage mere weeks after they met. The two seemed like they never even knew each other that well, and they were far too willing to overlook the obvious red flags being raised.

Mark and Nikki's Age Gap

Mark and Nikki from TLC's 90 Day Fiancé reality series.

There were plenty of issues with the relationship between the 58-year-old Baltimore resident Mark Shoemaker and his 19-year-old fiancé Nikki; Mark was overly-controlling, he seemed to be obsessed with his ex-wife, and, most importantly, he was 39 years the senior of his bride-to-be.

Eerily, Mark's children were older than his fiancé, and he did odd things like buying her the same model of car that his ex-wife drove even though she didn't know how to drive. Plus, Mark was outright domineering, regulating Nikki's life to the nth degree.

According to DailySoapDish, Mark and Nikki filed a lawsuit against TLC in 2017, as they believe their relationship to have been portrayed unfairly. In 2021, they seem to be mostly absent from the spotlight.

Pedro and Chantel's Family Feud

Pedro and Chantel on TLC's 90 Day fiancé series.

It's not always fair to allow a family's appraisal of a person to taint a relationship, but, when it came to Pedro and Chantel, the influence of family could not be ignored. These two clans absolutely detested each other, and, from a chicken foot fiasco to a literal fistfight, it's safe to say that these families just weren't destined to get along.

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However, the drama made for quite the storyline, and Chantel's family was eventually given a spin-off series on TLC, which premiered in 2019. While the health of the relationship isn't known, Chantel and Pedro are supposedly still together.

Molly's Family Couldn't Stand Luis

Molly and Luis from TLC's reality series 90 Day Fiancé.

From the get-go, it was clear that Molly's family did not care for her new boyfriend. Her oldest daughter was clearly displeased with him when they first met, and he never made any kind of attempt to rectify that negative first impression.

Molly's dad intimated that his daughter was purposefully ignoring Luis' red flags because she wanted a man in her life, and Luis caused irreparable damage when he asked Molly's daughter about her sex life.

Though they did tie the knot, the marriage didn't last for very long, and, as per InTouchWeekly, Luis remarried just months after breaking things off with Molly.

Jorge and Anfisa's Obsession with Wealth

Jorge and Anfisa from TLC's 90 Day Fiancé reality series.

Jorge and Anfisa have gone down as one of the most toxic couples in 90 Day Fiancé history. Neither of the two appeared to be genuine with each other, and the fact that they went through with their marriage despite their chaotic relationship came as a shock to many.

From the outset, Anfisa made it clear that she was only interested in Jorge's wealth. That's a red flag, to be sure, but Jorge deserves equal blame, as he put on airs and pretended to be much more affluent than he actually was.

David's Financial Woes

David and Annie do an interview In 90 Day Fiance

The match between the 48-year-old David and the 24-year-old Thailand native Annie didn't sit right with many fans. David was much older than his fiancé, and, though he didn't necessarily hide his financial situation from Annie, he never made the extent of his issues explicitly clear. David also struggled to curtail a drinking habit by which Annie was very off-put.

RELATED: 10 Ways Anfisa Has Changed Since 90 Day Fiancé

However, the two seem to have persevered, and, despite the challenges they've faced, they're still together and, as per TheThings, have engaged in some successful business ventures.

Ed Lied About His Height

Big Ed talking to the camera in 90 Day Fiancé series.

Edward Allen Brown, better known as Big Ed, is often vilified by fans of the 90 Day Fiancé series. Ed was twice the age of Rosemarie, and their relationship was strained from the start.

While he claimed that he wanted what was best for his fiancé and her child, Ed was dishonest about many things, and he entered into the relationship on dishonest grounds, having lied about his height online. He also claimed that he wanted a vasectomy despite the fact that he knew Rosemarie wanted more children. This Fiancé relationship was awkward for everyone involved.

Nicole Wouldn't Accept Azan's Culture

Nicole Nafziger Confirmed Not Together Breakup Azan In 90 Day Fiance 2

Nicole and Azan came from two very different worlds, and neither of them really seemed to come to grips with their partner's very different cultural perspectives and values. This was first evidenced by Nicole's desire for affection when out in public in Morocco, something with which Azan clearly wasn't comfortable.

Nicole openly admitted that she looks for lots of physical affection in her relationships, and Azan's more conservative views regarding romance should have come across as red flags for her. However, the two maintained their relationship for years despite this very obvious rift.

Azan Couldn't Accept Nicole For Who She Was

Nicole Nafziger and Azan Tefou talking to the camera in 90 Day Fiancé

Change can be a good thing, but there's only so much change a person could reasonably be expected to undergo. Azan was blatantly unhappy with Nicole's weight and frequently called her "lazy," and it became a major sticking point which the couple couldn't concur.

Nicole was unwilling to embrace her fiancé's culture and values, but Azan was equally guilty of being unwilling to meet his bride-to-be halfway. He always felt as if she should follow his commands to a T, and, rather than work to find a middle ground, he demanded that Nicole live up to the ideals that he set forth.

Paul's Awkward Behavior

Paul and Karine from TCL's 90 Day Fiancé series.

Paul and Karine are perhaps the most unpopular pair to ever have featured on 90 Day Fiancé; their personalities and lifestyles were completely different, and, to make matters much worse, they didn't even speak the same language, instead relying on a translation phone app to converse.

Beyond that, Paul's odd mannerisms should have been a huge red flag for Karine. From sprinting away after revealing his criminal history to infamously wearing a condom to go swimming, Paul didn't live life anywhere close to Karine's pace. That said, the couple is still together in 2021.

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