Sometimes everyone longs for things they don't have, never had, or perhaps lost. Perhaps try to acknowledge and accept those feelings. Find positive (and realistic) ways to reach for the things you long for. It is hard to give up unhealthy habits/behaviors unless you find healthy things to replace them with. If the healthy people in your life will spend time with you, take advantage of that. Find concrete things to do for them to show your appreciation. Read, see, and be with positive people and media/books. Do kind things and spend time cultivating your spiritual development. It's OK to be unhappy sometimes, it just makes us appreciate happy times even more.....