In Episode I we see the first flashback as Gar recalls an encounter with his now lost love “darling Katie Doogan”. The scene is fraught with sexual frustration as Gar tries to kiss Kate and pleads, “I’m mad about you! I’ll never last till Easter! I’ll – I’ll – I’ll bloody well burst!”
It is clear however that Kate is worried about whether they will have enough money to live on, and especially whether her father will accept her marriage to someone with so little financial stability.
There is an obvious contrast between the two characters and their priorities. Gar seems overcome by lust while Kate very pragmatically quizzes him about his income.
Gar loses his nerve before asking Kate’s father for her hand in marriage. Private tells us later - in the play’s real time - that Kate is now married and has become "Mrs Doctor Francis King".
She and her husband honeymooned in Mallorca, but as Private points out to Public, “you couldn’t have afforded to take her to Malahide”.
While Senator Doogan tells Gar that “any decision she makes will be her own”, we get the impression that Kate - like many women in her position at that time in Ireland - chooses her husband based on her parents’ wishes and to secure her future.
In Episode II Gar receives a visit from Kate who has come to say goodbye. Gar Private’s dialogue suggests that Gar still has fond feelings for Kate. But as the conversation turns to her husband, Gar Public lets his jealousy and resentment make him angry and cruel.
He loses his temper and begins raising his voice “rapidly, aggressively”, criticising Ballybeg and all who reside there. His behavior causes Kate to leave awkwardly as this does not seem to be the Gar she remembers.
Gar’s devastation at losing Kate seems to contribute to his decision to emigrate - on the day he agrees to leave for Philadelphia we find out that S.B. is not at home because he is at the wedding of “Senator Doogan’s daughter” and “some Dublin doc”.
The finality of losing Kate - symbolised by her marriage to Francis King - seems to be the catalyst for Gar’s decision to emigrate.