I feel for you ... It isn't easy getting it from all different directions, and not having anyone to turn to for help and/or relief makes it all that much more difficult.
I was one of the kids that was getting it at home and at school ... It was very lonely and tough growing up like that, and it still has lingering effects to this day.
You say you have one friend but don't want to burden them. Maybe it won't be a burden and perhaps they'll have ideas and solutions that you haven't thought of yet ... They may even be able to give you the name of a trusted adult you can talk to and might even go along with you for moral support.
Please don't suffer this alone ... It can be quite difficult to overcome later in life ... The sooner you are able to stand up to it, the better.
I definitely feel for you and will keep you in my thoughts and prayers.