She never seemed to sleep at night. She always tossed and turned and watched. But she never slept. She never let herself rest or relax. She was tense and always thinking. Glinda stayed close to her as she drifted to sleep and wondered what love was and what the hell it had to do with Elphaba Thropp.
The green girl's arm was draped across her waist in a gesture that made Glinda feel safe and secure somehow. At night when all was quiet and she could see the moon and stars outside the hotel's shabby window it was easy for her to think she was in love with her roommate. Why, the two of them had hated each other at first, but now... now the two of them curled together like kittens, Elphaba's hand lightly stroking her blonde hair.
But in the light of day, everything changes. Elphaba is exhausted from her refusal to sleep at night, and her head rests against Glinda's shoulder. She sleeps silently at Glinda looks out the carriage window. She can see the poor outside, struggeling to survive. She can feel the wind ruffeling her hair. And again her thoughts turn to love and Elphaba, but now they are different.
She touches the spun-coffee hair, and realizes she is not, in fact in love with Elphaba Thropp. The two of them are more than that. They were the flip sides of the same coin. One of them would not exist without the other. They were night and day, opposites. Glinda loved Elphaba, but was not in love with her. The two of them were... well, Elphaba always objected to having a soul, but Glinda knew if she had a soul mate, Elphaba was it.
Years later, an older Glinda walked out onto her balcony, lighting candle though she couldn't say why. She had a feeling of illness and a longing. Time had changed both women, two women who had both loved and lost and suffered. Far away, Elphaba Thropp was dying, literally melting to the floor.
A little bit of Glinda melted, too. She was never the same again.
There is one friend in the life of each of us who seems not a separate person, however dear and beloved, but an expansion, an interpretation, of one's self, the very meaning of one's soul. Edith Wharton