well i "self medicated" (on alcohol) my bipolar when not on meds. it led me to alcoholism so then i had two things/dx's to deal with simultaneously. what a struggle. but i succeeded with both, 20 yrs.sober and 20 yrs. with stabalized bipolar for the most part.
i use the analogy for ppl - if you drink to gain a feeling or drink to get rid of one, you're a problem drinker if not alcoholic/addicted. addiction occurs when no matter your good intentions when u drink u don't know when to stop, or drink til you're drunk, or have consequences as a result of drinking, etc. many of us also have had a compulsion to drink...like it's not a choice. other ppl addicted to alcohol can leave it alone for weeks at a time but when they pick it up the circus begins all over again.
so for me they can go hand in hand- self medication and problem drinking/addiction. also on meds it's not recommended a person drink...the alcohol counteracts the positive effects of meds.
so, imho, self medicating is gaining or losing a feeling by drinking and addiction has the component of gaining or losing a feeling. but a person doesn't need to be addicted. it is first a choice and later all bets are off if alcohol is abused.
i hope i haven't totally confused you. it's a good question. bear in mind i am basing some of my opinion on my own life experiences.