Welcome to the forum, Lily.
My sister is a heroin addict. I ignore her calls and texts all the time. Sometimes I just don't feel up to the challenge of listening to or responding to what she might have to say, and at those times I decide to just let it go to voice mail. Then later, if I'm feeling better, I'll listen to the message. More often than not I don't respond even after hearing the message.
Your sister is wreaking havoc on your entire family, and it has even started affecting your relationship with your husband. That's a lot of power you're allowing her to have. It's okay to take that power back and decide not to engage when she is being dramatic and accusatory. Engaging with her doesn't sound like it ever ends well, so perhaps it's time to try something new. I'm sorry that you have to deal with this, I know how much it hurts.
