Don't worry too much about handing down the abuse; you're in therapy, trying to work to prevent that, your mother was not (as they didn't have/believe in it then). I didn't have children partly because I was afraid since I'd learned a lot of my stepmother's angry ways. A lot of abuse is about "control" and I think most controlling people get that way trying to deal with anxiety. I can imagine your mother had a very insecure childhood/life and a lot of her (and my stepmother's abuse) was trying to get something in her life to come out "right" and the way she wanted it to. But abuse can also be because someone else is still being/feeling abused or anxious from higher up and the frustration and anger needs an outlet so a "safe" target is found. It's the old "kick the dog" trickle down and we children were on the bottom and safe to "kick".

Your mother didn't wake up one morning and decided to lie about her past to thwart her daughter :-) The lies and abuse are not about "us" and who we are, they just get tangled up with our youthful experiences of trying to make sense of the world (like abuse of them did theirs). It's very unfortunate but not a lot can be gained from blaming dead people for how we are now.

It is helpful to learn all one can about their lives to get the larger-than-us picture but "if they only hadn't done X I'd be okay" is a fruitless game to play as we can never know we would have been okay with that or how our lives would have played out had they not done X. Lots of knives cut both ways and I've discovered in therapy how much my stepmother's controlling behavior actually helped my unfocused/under achieving self get things done and made me feel safer from outside abuse or fears based on my own inborn, "timid" characteristics (my father's nickname for me before my stepmother even met me was "mouse").

Not just bad things happen alongside abuse, anymore than our symptoms are wholly "bad". We chose the symptoms to help us cope when we were too immature and inexperienced to figure out better ways and coping is always a good thing :-) That the symptoms don't fit us now is why we're in therapy.