New gp has cut my dose of 30mg Valium to 25- but is prescribing a friend 3mg of Xanax (alprazolam) with no problem- is this fair to pick & choose?

Your doctor is. Basing their decisions on the issues, symptoms and concerns that you have brought to him. Your friend is not you and has other issues that he is taking into account. Speak with your doctor if you are not sure the medication is the right one for you. It is not a matter of fairness, but clinical judgement, which is why he spent years in medical school and training.