Jerry had his share of girlfriends on Seinfeld, but the most important woman in his life was always Elaine. Prior to the events of the show, Jerry and Elaine were a romantic couple, but things didn't work out for unclear reasons. In the aftermath of that split, they managed to remain friends.
Despite Seinfeld avoiding many of those usual sitcom tropes, there always seemed to be a possibility that these two would get back together and live happily ever after. That never happened and it seemed they were not meant to be. A lot of the blame could be placed on Jerry for his many mistakes in their relationship.
Other Women
When a couple attempts to remain friends, there is always the awkwardness of seeing them with other people. Jerry and Elaine seemed to avoid that for the most part, but Jerry didn't always use the best judgment in these matters.
He would sometimes flirt with other women when he and Elaine were out together which is rude, to say the least. He always put other women before Elaine and she seemed to be annoyed with this behavior.
Not Understanding Their Relationship
Sometimes when two people find a connection with each other, the obvious reaction is that they should date. However, for some people, they should have taken a second look at the situation and realized that their connection is one of friendship rather than romance.
Jerry and Elaine seemed to make that mistake early on. They clearly get along great and enjoy each other's company. They make for perfect friends, but they misinterpreted that as romance at first and that set their whole relationship off on the wrong foot when they should have just been friends from the start.
Being Selfish
Seinfeld was a show unconcerned about making their main characters likable. All leads show themselves to be pretty bad people over the course of the show and Jerry is perhaps the most selfish among them.
This is true of his relationships as well. He is uncaring towards other people's feelings and really looks out for himself above anyone else. Though it didn't affect their friendship, Elaine would have seen where she stood as a romantic partner.
Blocking Out Their History
The show reveals very little about Jerry and Elaine's first romantic relationship. There are only vague mentions of it throughout the show, but that could be because it didn't make much of an impact on Jerry.
When Elaine is talking to Jerry about a friend of hers, Jerry is unclear who this person is. Elaine takes this as proof that he basically blocked out their entire friendship and can't even recall a friend's name from this period.
Proposing To Her
Thanks to one of his girlfriends, Jerry is put in touch with his emotional side and the results are quite shocking. He becomes a much more caring and loving person, especially to his close friends. This leads to him proposing to Elaine.
Jerry insists they were meant to be together, but Elaine is initially freaked out. After some time, she thinks it might not be such a bad idea. But by then Jerry is back to normal and takes back the proposal.
Trying To Have It Both Ways
After spending so much time together as friends, some old feelings inevitably come creeping up for Jerry and Elaine. They decide that they are mature enough to maintain a casual friend relationship yet still have sex like they used to when they were a couple.
As it turns out, they were not mature enough for that and problems quickly arise. The fact that they couldn't leave a good friendship alone nearly derailed their entire relationship forever.
Being Jealous
While Jerry doesn't seem to mind rubbing his flirting and relationships in Elaine's face, he often seems bothered by her relationships. While he occasionally gets along with the men Elaine dates, he can also be really jealous.
He hates the idea of Elaine dating someone whom she thinks is funnier than Jerry since that is pretty much all he has. He often insults her boyfriends and seems to think she could never find anyone as good as him.
Giving Her Cash
When Jerry and Elaine decide to reignite their relationship, they make a list of rules to ensure things go smoothly. Even with all the preparation, Jerry makes one huge blunder after another.
When Elaine's birthday is coming up, he struggles with what the right gift would be given their new relationship. Wanting it to be generous but not too romantic, Jerry settles on giving her a wad of cash. Obviously, it doesn't go over very well.
Sex To Save The Friendship
Just like revisiting their old sex life was a bad idea, Jerry and Elaine made the mistake of talking about their old sex life as well. This leads to Elaine admitting that she "faked it" with Jerry when they were together.
Jerry doesn't take this news well and becomes quite immature about the whole thing. Their friendship nearly crumbles, only for Elaine to suggest they sleep together one last time to save the friendship. It is another selfish move from Jerry.
Ignoring Elaine's True Feelings
Elaine can be just as mean-spirited and selfish as Jerry, but when it comes to their relationship, she seems to have complex feelings. Not only did she agree to marry Jerry before he took it back, she once admitted she wanted a relationship with him rather than just being friends.
Furthermore, when the group thinks they are about to die in a plane crash, Elaine seems ready to admit her love for Jerry. Jerry just seemed to ignore Elaine's feelings and went on with his own thing.