I experienced the exact same thing growing up and you know what worked for me? I started to realize that I began focusing too much on the crappy things they said to me and the times they poked me. I began festering in it and only noticing them they were picking on me instead of letting it go and acknowledging the good things as well. I began to resent my sister and my Mom and I am still in therapy dealing with issues of feeling picked on and left out of most of my childhood memories with them. I was a huge creator in that as I not only allowed them to affect me so drastically because of how sensitive I am, I also only focused on the negative and never looked on the bright side or gave them a chance which meant I lost out on a lot of loving opportunities with them. I don't know if this helps but I thought I'd share because maybe it'll hit home with you

All the best to you my dear & please let me know if there is anything else I can do!