Why did Ruth like Bettina but not other liberated women?

The brilliance again of my favorite drama series ever is that each year I watch, I observe new discoveries.

***POSSIBLE SPOILERS***

This round was Ruth's fascination and strong bond with Bettina (played brilliantly by Kathy Bates), but her hostile and discarded behavior towards similar outspoken, independent women - starting with Brenda (who she finally accepts on the LAST episode, save for that season 2 episode where she says she loves her at the pre-wedding party).

Illenena Douglas's character (The New Person) was awesome! Yet Ruth (and the rest of the Fishers, minus Claire) treat her horribly. Douglas is blunt, funny and inappropriate- but she does amazing work. Ruth despairs her when she gets relationship advice at the dinner table. Bettina however, is always telling Ruth to let her hair down, change her style of dress, relax, and even STEAL from department stores! Ruth loves it. But let her sister Sarah (again the brilliant Patricia Clarkson) come up in subject, and Ruth goes back and forth. Sarah is the BIGGEST liberated woman of the series. The hippie with a Vicodin addiction, who wants to inspire everyone around her, and "was in Peru" when Nathaniel Sr. was tragically killed in the first season. But Ruth even warns daughter Claire that "Aunt Sarah has no boundaries and you shouldn't take her seriously." But then Bettina will show up, and Ruth says "Let's go to Mexico!" She's so back and forth in her personality, or what she will tolerate. Not to sway off subject, but even when she was giving the intern Arthur a tour of the house, when they come to his bedroom, Ruth abruptly says "Okay. That's the end of the tour! You're on your own now." Whoa.

Let's also examine Brenda's mother, Margaret (AGAIN the amazing Joanna Cassidy). The latter is JUST like Bettina. Both are foul mouthed, tell it how it is feminists who live life as it is and not bottle their feelings. But Ruth ONLY seems to be able to let go a little with Bates is around. With Margaret, Ruth "looks at me like I just took a dump on your front lawn" lol!!! As Margret puts it at an art show when they first meet.

Frances Conroy, who should have easily won the Best Actress Drama Emmy awards for season 1, 2 and 5- is able to embody Ruth in a colorful arrangement of emotive expressions and outbursts. She's one of the comic reliefs of the show, and I would pay top dollar to JUST watch a series about her, Sarah and Bettina and their continued adventures after the 5th season wrapped (despite the fact that we know what happens to the main characters later on in life). Ruth ALSO behaves this way with Nickolai, the steamy Russian she dates that is terribly rude, sarcastic and sexual with her- something Ruth seems to hate and like at the same time.

Any insights?