Frustration! Hands tied!

I have been reading and learning and trying to turn my attention back to me and what I need to do to survive this (vs what she needs to do). But it is so hard when she continues to learn nothing and keeps putting me in unhealthy dynamics...namely parent/child dynamic....for which I am really trying hard to work against! So here is where this week worked out: WE have been in the middle of buying our home, where we live and run our business from (a child development school). It has been a very long process with many delays (not good for someone with ADHD in terms of holding their focus). Since my credit is better, the home will be in my name and they are looking at my credit, etc. WE/I have been told not to buy anything unnecessary and to not use my credit cards except for justifiable emergencies. SHE, however, is free to use hers! And use them she does!! She has a 7 year old and it is back to school time. This week I observed her on her iPad a lot and closing it out as soon as I walk in the room. As well. I saw her looking up shoes online. When I ask her what is new today, she says "oh, nothing". Ya right! I can guarantee that in the next few days many packages will appear at our, shoes, jackets, for her son...FINE....would I have liked to be included in this...sure, of coarse...but I can let that go. The thing that gets me, is I will bet anything that along with shopping for her son...she bought stuff for herself! As well she told me she asked her son what he wanted to do with his last weekend before school and his comment was he wanted to buy a new xbox game....she asked me if I was okay with that. I new she was lying!!! thing I know there are 3 new games (that I know of)....SHE is staying up late while I sleep (all of a sudden her acid reflux is acting up) and she is commenting on how long it has been since she last played xbox. Who were the games really for?? And here I stand not being able to buy anything!! So WE can buy our home! I ask myself how I got talked into all of this! When did she express to me that we would be in this as a team and How did she lead me to believing her? This week we have been extremely distant! And she asks ME why I am distant. I wan to say "because you have made all these choices and decisions without me and have spent money on you and your son when you know I cannot and this kills the team!" But she would just lie and say she did non of that and get mad that I seem to always blame her and never take responsibility for myself and my actions. TELL me....what could I have done differently? I didn't say anything about my assumptions or what I think might have happened (based on consistent actions), I accepted that I agreed to do this and it is just my decision that has led to her being able to buy stuff and me being financially frozen. I can't help that this type of behavior sets us apart and not functioning as a a grown up adult partners. And I also can't help that her looking me right I. The face and lying to me creates a distrustful and betrayed feeling for which....why wouldn't I pull away! Why would I snuggle up to her when, there is a very good chance, she looked right at me and lied to me...or told me some half truth! As it has been in the past, she tells her son to not tell me that they bought something....a new game....or stayed up late playing the new game while I slept (and I mean til 2 in the morning). So then that creates a THEM AGAINST ME MENTALITY" they are the siblings who are in it together to pull the wool over moms eyes. I DONT WANT TO BE THAT TO HER!! I WANT TO BE THE ONE WHO BREAKS THE RULES WITH HER! THAT IT IS HER AND I AGAINST THE WORLD....NOT HER AND HER SON AGAINST ME! I am working so hard to not be in a parent child dynamic, but SHE puts me in that role and it really breaks our bond. It breaks our connection and it waters down and changes who WE are......who we were last week. I hate to say it, but the weeks her son is here this always happens! The weeks he is not here we can be more of an equal couple and she tends to do more work at joining us together and seems to view us as one. United, in love, etc. the weeks he is is her and him....and I am some one to get around...someone who stops or blocks them from having fun and being happy. Maybe I am wrong....maybe she didn't buy a bunch of stuff....maybe she really did buy only a few games for him.....but I doubt it! And isn't that the shame right there....that I can't ask and trust I will get a truthful answer or that it won't turn into a fight to deflect the problem onto me! Isn't it a shame that I can't trust her to be in this house buying situation with me!! And that I am just waiting for the packages to arrive and wondering what lies and excuses she will tell me looking right at me! And that I won't be able to say "LIAR". And that really ....I dint care!! Just fuckin tell me the truth and involve me!! DONT PUT ME IN THIS STUPID PARENT CHILD DYNAMIC for which I am working really hard at avoiding! STOP! I AM NOT YOUR MOM! I am not the fun buster :(