I've been dealing with a bout of this recently.
For a while, my wife and I have wanted to start biking locally (previous apartment had no space for a bike, did not allow bikes to be chained to the pillars in front of the apartment) but neither of us have bikes - facepunch me, please!. Well, she does - the bike she used as a teen was still at her parents' and is in serviceable condition. I've long since worn out every bike I've owned. So, I'm in the market. I've been surfing the 'list for a few weeks and the local pages are just dead for what I'm looking for. Average 25-35 new listings a day, half of them kids' or BMX bikes. Local bike shops are too pricey for someone who only is going to be a casual, 3-5 mile per trip rider towing a kid in a trailer. I've been anxiously browsing new entry-level bikes and the thought of spending that money does not make me feel good.
How much? $600 for a bike & accessories (trailer, helmets, lights, etc.). I grabbed a trailer off NashBar with their April Fools' sale but still am fearing spending a few hundred on a bike for myself. A bike! What am I turning into!?!
It's hit me with other things - lately I lose sleep on anything over $100 that isn't something I need to survive.
I've come to realize that it's a side effect of a frugal lifestyle - cheapness (some also call it "analysis paralysis") - the need to make the most efficient, optimized choices all the time. The need for all the facts, no ambiguity, and no ill consequences of your decision. In my case, I could get a $10 junker wal-mart used bike that has broken brakes and a bent handlebar, and I could live with the choice knowing that I get so save some more $$$ for my future self. But, will my future self appreciate the back pain and cuts/bruises from the junker bike over a lightweight, functional bike that fits? Most likely not.
Using tools & skills learned here, anyone can buy a junker car, or a foreclosed house and with enough muscle and determination make it work and come out ahead. But will you appreciate yourself afterwards? Will the payoff be there? Probably not.
I guess it's ultimately what separates those who are comfortable with the frugal lifestyle, and those who can't or won't do it. Frugal folks have to be talked into spending money; many others need to be talked out of spending money. More often than not, I have to ask my wife to talk me into buying something that I logically know is the right choice.