Countess Lydia was married to her husband at a very young age and genuinely fell in love with him.
For reasons no one quite understands, though, her husband left her. Countess Lydia was crushed. They're now separated and never interact.
Ever since, Countess Lydia has always been in love with someone. She especially goes for anyone who's distinguished.
Lately, though, she's been feeling as though she's never been in love with anyone the way she's in love with Karenin. She appreciates what she perceives to be his high, lofty soul.
This love proves itself by the way that she has started dressing carefully in the morning. She blushes when he enters a room and when he compliments her.
Countess Lydia discovers that Anna and Vronsky are in Petersburg and gets upset. She takes great pains to hide this fact from Karenin and to make sure that his path never crosses theirs.
Countess Lydia is pleased when she learns that Anna and Vronsky will be leaving the next day, but this joy is cut short when she is handed a letter from Anna, begging Countess Lydia to engineer a meeting with Seryozha.
The letter appeals to Countess Lydia's generosity and explains that Anna hasn't turned to Karenin with this request because she doesn't want to wound him further.
Countess Lydia tells the messenger that there is no answer, then writes to Karenin that she must meet him. She says they can talk at the birthday reception to be held at the Palace.
Countess Lydia likes writing letters to Karenin: she feels that letters add an air of mystery to their communication.