You need a tree expert..................they might be able in the bitter cold of winter to trim 1/3 off and spray the cut area with paint, should be cut on an angle..............that will take the weight off the tree and they might be able to put a long screw with a bolt to brace it together...........this is soft wood................I don't know if something that high would be safe..........that's why I am saying you need a tree expert. Go on line and put your concerns in there............you might get lucky with a better answer.