Throughout the play Stella is torn between her husband Stanley and her sister Blanche. She loves Stanley and sticks by him constantly. She also loves Blanche but she does not want their relationship to remain in the past, Stella has moved on and wishes Blanche would do the same thing. During the whole play Stella always choices Stanley over Blanche.
One price that Stella has to pay for continuing her marriage to Stanley is the guilt of always choosing Stanley over Blanche. From evidence in the text and Stella's attitude we know that Stella understands how Blanche needs to feel loved. Stella knows that by choosing Stanley, Blanche will be hurt, Blanche needs to feel loved and to her it would seem that Stella is turning her back on her.
Stella choosing Stanley over Blanche is evident when Stella sleeps with Stanley after he has just hit her. Blanche is horrified by his actions and immediately wants to look after Stella: "Blanche screams and runs into the kitchen," "lunacy, absolute lunacy." This shows us how ignorant Blanche is towards Stella and Stanley's relationship as we know through Stanley's friends that the violence has happened before, and has just become part of life now. Blanche cares a lot about Stella, she sees her as a source of love and so is shocked that Stella puts up with Stanley treating her like this and wants to get her out. But Stella choices Stanley over Blanche and sleeps with him rather than leaving with Blanche. .
In scene three we hear Stella being hit by Stanley, and Mitch telling Blanche that "it's a shame this had to happen when you just got here. But don't take it serious." This indicates that this is not the first domestic violence between Stella and Stanley. This obviously is not a great point in their relationship but Stella is still with Stanley proving that this is another example of what Stella has to deal with for her continuing marriage to Stanley.