Can you get aids from sharing an acne cream with somebody?

No. Hiv is fragile and is generally transmitted with a live human cell which the acne creme will probably kill in any case. Despite the "theoretical" risks of mosquitoes, toilet flushers, toothbrushes, bars of soap, etc., etc., people who live with hiv-positive folks (even very sick ones) but don't exchange body fluids don't seem to catch the disease. And sharing's good. Glad you asked; best wishes.