I think for some BPD people drinking heavy is easy and very very fun.  But it can really ruin your life, job, bank account, health, etc.  I've smoked weed for 10+ years w/"the usual" effects.  Stay up too late, introvert, etc.

In the ~5yrs Ive drank heavy the price has been very heavy.  Tens of thousands of dollars spend on booze and things related.  Damage to personal relationships, my career, etc.  Ive almost been in serious car accidents, get in stupid fights with my gf (who also drinks too much) and so on.

On pot I learn.  I read, I educate myself - etc.  On booze I just get in trouble.  I've had several alcohol related injuries (falling, etc) even though I am a very stable person and work on my balance a lot (yoga, etc).

In short - when it comes to booze its probably best to keep your cruising altitude at 2 or 3 drinks, nice slow pace.  my 2 cents