This post contains spoilers for Seasons 4 to 7.
While the original love triangle in the series was supposed to be Ivan, Carolina and Marcos, the story fizzed out when Season 3 began. The boys were best friends to the point where Carolina was jealous of Ivan's closeness with Marcos. After that, the story consistently demonstrated the strength and depth of Ivan and Marcos' friendship to the point where the finale closes on them reuniting. The development of their friendship was one of the keystones in what made watching the series so great.
From the moment Julia arrived at Laguna Negra in Season 2, Roque only had eyes for her. Unfortunately for him, Julia ended up falling for Ivan instead. From that point, Roque's relationship with the rest of the group started to deteriorate, and it really set in motion his downfall and betrayal of the others. While everyone insisted that Roque will eventually get over Ivan and Julia getting together, he never seemed fully over it. Since both were his best friends, he didn't turn to either of them with the truth of Noiret's disastrous plan, culminating to his murder of Carolina. Later, when Roque discovers the truth about Garrido, he couldn't go to the others and ended up dying as a consequence of spying alone.
Ivan and Julia didn't help the situation much either. Ivan constantly acted as if things were normal between himself and Roque, which is how Ivan obnoxiously would deal with any situation going wrong in his life - his father's abuse, Carolina cheating with Marcos, his hooking up with Julia, etc. Julia, on the other hand, really didn't give Roque much attention except when she and Ivan were fighting. This contributed to Roque becoming distant enough that he didn't feel as though he could turn to them for help anymore.
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