1) Addict 2) Addict or bully 3) Any excessive drug user 4) Bully 5) Bully or addict 6) Candidate for rehab 7) Drug addict 8) Exploitative type 9) Hurtful sort 10) Improper handler 11) Maligning sort 12) Maltreater 13) Manhandler 14) Mistreater 15) Mistreating type 16) Offender 17) One indulging to excess 
• (n.) One who abuses [in the various senses of the verb].
A·bus'er noun One who abuses [ in the various senses of the verb]. 
[n] - someone who abuses
Someone using alcohol unhealthily, potentially as a coping mechanism. Example: Recognizing oneself as an abuser during stressful times.
maltreater noun someone who abuses