DMKK,
Few things....
First off: WELCOME. this is a super-duper terrific site.
Second:
"It's just hard when you get cheated on to know they are happy and thriving and you are suffering and lonely and all that."
umm.....not.
believe me, she is absolutely not thriving, nor is she truly happy. happy people are grounded. grounded people know what they want, they have integrity because they know they have to look in the mirror every night.
Third: as some have said, they can't say whether or not she is alcoholic, but......
well...she is.
Now you know the truth. I think the purpose to ask all these questions, and analyze the relationship, is to learn and grow. And not go into your next relationship repeating.
Peace,