Excluding Friend from social event

Title sounds harsh but let me elaborate. Throwaway for obvious reasons but I have a close friend with bad habits (Drugs, Alcohol etc.) I still see him every now and then but I recently started to expand my social life and circles to get away from that type of lifestyle as I've changed. 2 weeks ago he asked me if I was doing anything and I said we could grab a beer. Later I was going to another social event and invited him because he wanted to do something and I felt bad. Now he regularly shows up and I kinda feel uncomfortable as hes not really changed and I feel I lost my "safe space". What are your advices to communicate in a friendly way my feelings.