Richard's Last Act if Control
Despite fighting AIDS for so long, Richard is declining fast and is starting to lose control of both his body and mind as they degenerate. Ironically, although his death is coming fast he commits suicide, taking his own life instead. This is his last ditch effort to have some control over what is happening to him.
Virginia's Depression
Leonard is worried that Virginia is becoming depressed and unable to write or channel her creativity in the hustle and bustle of London and so insists that they move to the quieter suburbs. The irony of this move is that Virginia is going steadily mad in the suburbs and has terrible writers block because she is homesick for the city and cannot concentrate, the relocation having the opposite effect from what was intended.
Laura's Perfect Life
Laura has a perfect life from outward appearances; perfect husband, perfect child, perfect home. This is irony because from Laura's perspective her life is anything but perfect and she would like to escape from it and have a do-over. The irony is the discrepancy between what her life looks like from the outside and what it feels like for Laura whilst she is living it.
Clarissa As Stereotypical Wife
Clarissa has an ostensibly non-conformist lifestyle as she is in a committed relationship and living openly with another woman at a time when this was not a widely accepted thing to do. The irony here is that within this non conformity is stereotypical domesticity as she is the "housewife" in the relationship and fits into the societal box of home-maker and as if she was in a traditional heterosexual marriage.