It’s clear that the silent treatment or being intoxicated 65% of the time has not succeeded in gaining your family’s attention so a different approach is necessary. You may think you are giving off strong signals that you are upset but it is possible that your parents are interpreting them differently. They may see it as you just being angry or have trouble seeing that you are also struggling in addition to your sister. Blaming you for ruining the sweater doesn’t seem fair and must have really hurt your feelings.
The best way to approach the situation is to let your parents know that you have been feeling jealous of your sister. It would be very important for you to empathize that you really care about your sister and don’t like feeling this way. There seems to be something about the family dynamics that prompts your jealousy. Family therapy would be a great way to understand the underlying issues and help everybody in the family communicate more effectively and show mutual support for all family members