Past is Prologue - Buck and his partners
"Why does this keep happening to you?...No, I'm gonna tell you why. Because you don't talk to the women you're dating. You just go with the flow and find yourself in a relationship with no idea what to do when things go wrong."
Bobby says this to Buck in S5E9, Past is Prologue. This is the hamster wheel Buck can't get off - hell, it's right there in the title of the episode. The episode ends with the love confession from Taylor, which was awkwardly returned by Buck with one of his patented deer-in-headlights expressions. One episode later, they both are begging for help selecting Christmas gifts for each other. Two episodes later, he kisses Lucy, panic-invites Taylor to move in with him, and everything goes downhill from there.
The thing with Buck is, even as he grows up, even as he gets more confident professionally, even as he establishes himself as a fixture in the lives of the 118 - knows he's loved by them - he still does not believe that someone can really know him and be in love with him.
When he was with Abby, he didn't really know himself. That's part of why that relationship - that love he had for her - was so transformative. He had no idea he was capable of loving like that, of stepping inside with someone, of standing up and being strong, and he liked that version of himself. He saw that version of himself as someone he could respect, someone maybe worthy of being loved back. Then he became terrified of letting go, of sliding back into Buck 1.0. So he held on, for months after she told him to move on, as the calls became less and less frequent, as his sister and his friends all told him she was gone.
(But he didn't relapse. Sure, he slept around a little bit, but while he did so he was stepping inside with someone else, standing up and being strong beside someone else who needed him - Eddie (and Chris). He provided the foundation for Eddie and Chris to be able to stay in LA, by introducing him to Carla and being there week in and week out for the two of them. Still, 6 years later.)
Ali was little more than a fling, same with Natalia, but Taylor - Taylor is, ultimately, the relationship that most closely parallels Tommy. With both of them, you have an awkward dinner that ends with Buck being left behind after behaving badly in front of his friends (Taylor with Albert and Veronica, Tommy at Miceli's the first time). You have a kiss Buck wasn't expecting, followed by the other leaving the loft immediately. And you have a rushed invitation to move in, in which Buck acts very distinctly like there's something wrong and in which each time his partner was surprised. In both cases, the ask to move in was the beginning of the end, though with Taylor it was obviously a much slower demise.
The primary issue with both relationships continues to be the lack of communication, on both sides, not just Buck. Taylor doesn't tell Buck about her father or family, and Buck just - doesn't ask. They were together like 6 months before he finally said they needed to have the conversation, after Bobby's prompting, and she admitted to her family tragedy. That's a significant period of time to not learn literally anything about a partner's family.
Buck and Tommy are on their 6 month anniversary date before he finds out that Tommy is gay, not bi, and that he was previously engaged to a woman (and that that woman was Abby). All stuff that, in a serious relationship, would generally come up fairly early on if the communication is at all there.
Then you have each partner not respecting Buck's boundaries. Taylor moving in and making Buck get rid of his couch to keep hers. Taylor saying that the Jonah stuff will be off the record, then betraying that promise. Tommy calling Buck Evan without us ever seeing a, "hey, you can call me Evan," line from Buck, even though in season 4 he tells his parents that people who know him call him Buck. Tommy not knowing that Buck hates basketball and gifting him tickets, because Buck never said, "by the way, I think basketball sucks and that's why I only showed up that one time," and Tommy never bothered to learn what Buck's actual interests are.
Because Bobby is right. Buck doesn't talk to the people he dates, not seriously or honestly. Buck makes himself small in his relationships. He's so afraid of being left behind that he becomes translucent. He's honest and serious and real with Maddie. He's honest and serious and real with Eddie (hence why he was so distressed about lying to Eddie about Tommy), and with the 118. But with Taylor, the honest and serious bits were later in the relationship, after prodding from outside sources, and with Tommy they never happened at all.
Compare this to other relationships on the show. We know that Hen told Karen about Eva on the third date. We know that Athena knew about Bobby's previous family and losses before they ever got together, and that they shared faith. We know that Maddie and Chimney became close friends first, having their buffridays and finishing each other's sentences, with Chim knowing about Doug and all that first. The early-established depth is there in all the other relationships on the show, but it's not there for Buck or for Eddie..
The thing is, I'm not a Tommy hater, and I'm not a Taylor hater. They both were good examples of superficial romantic relationships, that contrast sharply with all the rest of Buck's relationships, and the other romances on the show. It was Taylor who said that Buck's life was full of meaningful relationships, and she was absolutely right. But in order for Buck to get off this hamster wheel - in order for past to stop being prologue - he needs develop depth of relationship first. He needs to be solid, and trust that he's not going to be left behind. And frankly, he's not ready to do that yet, though I hope that this breakup may be some impetus for him to look into that more deeply.
I hope the show has the grace to get him there. I think it will.
