Repeat same mistake over and over again.
READ AL - nowhere does it state that adultery is good or acceptable.  Instead, it lays out a process that may provide some guidance and lead via context, situation, etc. so that a faithful catholic (divorced) might be able to share the eucharist.  From this, you knee jerk to unreasonable all or nothing thinking.
AL is NOT about divorce - you do not get it.  My citations show that divorce did exist via cultural, monarchies, kingdoms, etc. built in laws and customs.  The Church existed in those times and one way to deal with these situations was to implement the sacrament of matrimony which later centuries set into law, etc.  There was no church canon law until the 20th century - divorce existed.