This Is Us features several romantic storylines but, at the center of them all, is the love shared between Jack and Rebecca. These two are the literal source from which most of the love stories in the show spring--they are, after all, the parents of the main stock of lead characters--but they are associated with being the iconic, classic image of true love as if all relationships existing outside of theirs are merely a trickle-down from the purest source. This is, of course, a lot of stock to put into one couple, however.

RELATED: 15 Shows Like This Is Us You Need To See

Bec and Jack deserve a lot of the fanfare their relationship gets, but to measure all love against theirs would be a mistake. Each makes their own fair share of mistakes in the relationship, and even if their romance is beloved by many, it is by no means perfect.

They're The Perfect Couple: Bec Fixes Jack's Birthday

Rebecca and Jack arguing

Bec suddenly realizes that she has completely messed up Jacks' birthday, and this isn't something that happens in their relationship.

Bec, being pregnant, is out of sorts and not acting her usual self--but as soon as she discovers her mistake, she immediately wakes up to her true priorities and does her best to make it up to the person she loves.

They Aren't: Bec Forgets Jacks Birthday In The First Place

Jack and Rebecca

Bec forgetting Jack's birthday in the first place proves that their relationship isn't perfect.

It isn't just the slip-up that makes the day unfortunate, but rather that on top of her blunder Bec also treats Jack with the utmost contempt all day leading up to finally fixing what she's done.

They're The Perfect Couple: Love At First Sight

Jack and Rebecca

Whether one believes in love at first sight or not will paint Jack and Bec's relationship differently, but for those who do, the way they meet is a true tear-jerker.

RELATED: This Is Us: 10 Of Jack Pearson's Best Quotes

Seeing Bec singing literally stops Jack in his tracks from committing a crime that would have changed the course of his entire life. Instead, the course of his life was set toward committing himself to loving Bec and building a family with her.

They Aren't: Jack Makes Decisions Without Bec

Rebecca upset

It might seem like Jack's huge gestures of saving the family are romantic, but at the same time, it shows that he is leaving Bec out from a large part of the decision-making of their lives, such as when Jack buys a house for he and Bec to raise their family in.

Luckily, this works out--but Bec had no opportunity to have a say in the matter, presenting an inequality in their relationship.

They're The Perfect Couple: Jack Tries To Sober Up For Bec

Jack and Rebecca from This Is Us sitting down for a candlelit dinner.

Alcoholism takes a toll on relationships and is a great struggle both for the addict and the spouse. Jack tries to take on this challenge all on his on the first time around, going to boxing after work as a way to distract himself from the need to drink.

The effort he puts into bettering himself for her exemplifies how important she is to him, and how strong their relationship is.

They Aren't: Jack Keeps His Problems To Himself

Jack and Rebecca in bed

Jack trying to cope with his alcoholism alone seems valiant in some respects, and at other times comes across as infuriating for fans, showing a lack of trust in Bec and even a fear of her.

He doesn't allow himself to be vulnerable enough to it to her that he is genuinely struggling, at least when he first attempts to overcome his drinking problem, suggesting a weak point in their connection that leaves him suffering.

They're The Perfect Couple: They Share Similar Parenting Values

Jack And Rebecca happy together

It does not automatically follow that two people who make a compatible couple will also become compatible parents.

RELATED: This Is Us: 10 Best Characters, Ranked

Many may find that, upon having kids, they actually find themselves in a conflict that their relationship has trouble withstanding purely because of differences over parenting practices. It makes Jack and Bec's relationship even more solid that they mostly agree on how to raise their children, and that it even brings them closer.

They Aren't: They Pick Favorites

Jack and Rebecca

Jack and Bec majorly agree on parenting, but they do fall into the common parental downfall of picking favorites amongst their kids.

Bec repeatedly favorites Randall over the twins, in some ways Kevin feeling left out.

They're The Perfect Couple: They Work To Stay In Love

Jack and Rebecca dancing

As much as two people start out loving each other things can always fall flat. Jack and Bec love each other, but they face stagnant points in their love for each other--love doesn't always mean being in love, necessarily, as viewers can see from how the couple changes from season one.

Making an effort to bring back the spark instead of giving up can make or break a relationship, and Jack and Bec do their best to always come back to one another and prove their love instead of taking the easier road and walking away.

They Aren't: Bec Lied Their Whole Marriage

This is Us Season 4 Jack, Rebecca, and Randall

Jack isn't the only one who kept secrets during the marriage. Bec kept, arguably, the biggest secret of all, keeping Randall from his father as if she didn't know where he was--even when Jack asserted that he though Randall should have a shot at meeting his birth parents.

Both Jack and Bec kept things from each other that were vital to their lives, a sign that, despite what many fans would like to believe, they were by no means perfect.

NEXT: This Is Us: 5 ing Characters We Love (& 5 We Don't)