I am sorry that your sister's input has created a deep challenge in you. I have had that problem myself because going all the way back for me my older sister was bossy, could be mean and critical.

When we are very young and have a presence in our lives that is critical be it a parent or sibling or even a teacher or piers, we can develop an inner critic that can expect to be criticized or put down in some way. The saying, "We may forget what another person said, but we never forget how it makes us feel" is so true and can be something we carry our entire lives.

It's important to keep in mind that children are narcissistic and with siblings can get jealous and try to manipulate for attention. Children don't know this and can be sensitive and "believe" they are "less than". A lot of emotional challenges and deep sensitivities develop from a very early age. It can lead to a deep feeling that anytime one does something productive or positive to expect a presence that will "hurt" them or tell them it's not good enough or even laugh at them.

The first step is identifying this challenge so you can see it for what it really is, which is often "jealously" and a desire to remove whatever takes away attention and praise. This can be a challenge as often this "feeling" can be strongly imprinted.