Donna Freedman recently wrote an article on Get Rich Slowly exploring how people come up with a variety of external problems to excuse themselves from taking responsibility for their own actions (or lack thereof). She says that we need to call BS on our excuses because usually we are the victims of our own decisions.
I have been guilty of this many times in my life. When I was an undergraduate I had to have some expensive dental work that ate into the depths of my student overdraft. But that's the BS talking; it was ME who neglected my teeth and ME who didn't have any money saved for emergencies!
More recently, I've found when tracking my spending that I often overspend on fuel. In the past I would estimate the cost of getting to work and back, then add on another few miles' worth of fuel per week and budget that amount. Every month when I went over budget I would say, “Ah, but last month I had that trip to Redruth / worked more often / had to go to town a few times” etc. Every month there was an “unexpected“ reason why I had spent too much! I learned that while I do try to limit my driving I cannot stick to as tight a budget as I believed I should, so I have had to adjust my budget accordingly.
I can foresee similar BS justifications in our new place. It's very easy to get carried away when hunting for house stuff like kitchenware. It has been useful for us to go as a couple, with one pointing out to the other that no, a huge meat cleaver is a want, not a need (especially when one of us is a vegetarian!). Better to save that money for next month's rent!
It really doesn't matter what mistakes you've made in the past. The best thing to do is try and learn from them, rather than burying your head in the sand telling yourself it wasn't your fault. Got an unreliable car? Make sure you have money set aside for the inevitable repairs and eventual replacement to avoid taking out a loan. Got a bad credit rating? Save up a couple of months' worth of payments on your debt so you'll always be able to pay at least the minimums.
Don't be afraid to say yeah, I screwed up, but here's why it won't happen again.