utter confusion: are we separating?

[terran23]

any advice is welcomed and appreciated, but more than anything i just neecd to tell the story and vent it - she and i fell in love last october, and we moved FAST - moved in with her after a couple of weeks - had major surgery in december which she nursed me through - we are both alcoholics, she has a 12-year old son - she is a wonderful woman and i love her a lot - BUT - i have major trust issues from past relationships with family/lovers, and am also a fairly intelligent person, over the years i've learned to detect a lot of typical deceptions - i am 34, she is 33 - back in october, the first time we made love, that night at the bar she got drunk and went home with another man; i was devastated and considered leaving very seriously - she explained it, she apologized, and i let it go, even though it hurt a lot, and continues to every time i think about it - a month later she was 'out with friends', getting wasted, and i texted and called repeatedly because around 2 in the morning i started to be worried for her - she didn't reply, and when she came home, i did something wrong for the first time - you all know what i did, right? i looked at her phone - she said it had run out of batteries and that's why she didn't answer me - this was untrue - i confronted her the next day, and we had a long talk about honesty, and i told her if she lies to me we have no chance as a couple - she and i are good to each other ALMOST all the time - well, 2 nights ago i wasn't very good to her - after spending my entire morning lecturing and training her to TAKE ACTION to stop her son from failing at school, and listening to them for hours go through their quarterly ritual of doing his homework for him so he won't fail, i broke down and went out to get drunk - she picked me up later, got drunk with me - we came home and got in a huge fight, and she left, didn't come back all night - she claims that she slept in her car, which is logically plausible - but my gut tells me that she went to be with someone else, and when i looked at her phone she had deleted her texts from the night before - when i confronted her about this, she said that she knew i would look at her phone, that she deleted the texts to punish me for being a jerk, because she knew that it would drive me nuts - well it has - my instinct is that she did something she regretted immediately, and deleted the texts because of truly damning evidence that she feels would cause me to leave her, something i have unfortunately threatened to do every time we have ever fought - i spent the next day(yesterday) trying over and over to get her to talk to me, but she got drunk instead and went to sleep - the classic liar signs were all there, no eye contact, physical blocking postures, etc. - this, coupled with the crazy 'i deleted my texts to punish you' story, has made me all but sure she is lying to me - it seems more likely that she deleted the texts so that i couldn't read them, because if i did it would cause (more) serious problems for us - i'm ashamed of having spied on her, but she did break trust with me and now i'm just wondering if we should separate - she says she doesn't want to do that and that she loves me, but i am having a hard time with this - i don't know if i can let it go, i think i will always wonder, and i don't want to spend my life with someone i don't trust to be honest with me - i fault myself for weakly getting drunk to assuage the tension of that day, and i fault her for waiting til the last minute to try and teach her son to be responsible for his schoolwork - he is an awesome kid and i love him, but he has a pattern of lying about his homework, and she has never punished him - between her and i both owning significant booze problems, and me finding the stepdad role to be pretty unpleasant a lot of the time, i don't know what to do - she helped me through the most awful time in my life in december, and i WILL NOT abandon her or the boy, but I am wondering if i should move out and just help with money - it's obvious to me that both of us shouldn't drink AT ALL, but every time i try this it lasts for a few days, then it's more of the same - she still maintains that having a drink now and then is not a problem, but it's very obvious to the world, our friends, that it is the main problem in her life, when i started seeing her it was intense, and something stupid that i did with her - when she drinks she is capable, even likely, to lie, and she was HAMMERED when she spent the night out two nights ago - thanks for reading, i am going through all the physical breakup pangs yesterday and today, and feel very sick - i love her dearly and don't know what to do now