Describe the relationship between Jinx and Iris in Bitter. Were they in love?

Iris and Jinx love each other and share a deep bond as a result of their mutual secret of the role they played in Little Red Garlock’s death. In fact, even prior to Little Red’s incident, Iris had a crush on the handsome Jinx, whose basketball prowess earned him popularity at school. Even though their attraction to each other blossoms further after Garlock’s murder, the two conceal their feelings and hardly ever meet or exchange words. Of course, the odds were against them, considering the racial segregation at the time.
Years later after continuing with their different paths in life, Iris and Jinx continue to feel a strong closeness to each other. Despite her marriage to Alan and settling into a prestigious family, Iris’s heart is with Jinx. At one point, Iris reaches out to Jinx in an attempt to comfort him. She tells him to let go of his guilt and says that Garlock’s murder is her fault.

I'm the one. I'm to blame. Not you.

It is not until Jinx joins the army and is deployed to Vietnam that the two admit their love for each other. He sends her a photo and on the back he leaves her a note: "Honey – Think I’ll ‘pass?" Iris then breaks down in tears and admits her feelings for Jinx to her uncle.
https://www.utupub.fi/bitstream/handle/10024/74862/AnnalesB343kahkonen.pdf?sequence=1&isAllowed=y