A lot of philosophy only holds true if one's basic needs are fulfilled. You could easily claim "I can be happy with whatever happens in my life" if you've got a sustainable lifestyle. It doesn't even have to be lifestyle- or hierarchy-of-needs related. In my case, I can control my happiness level perfectly while living in a very tiny apartment and spending a disproportional amount of my salary on living and commuting, but I can't convince myself to be happy if I'm trying to sleep and there's a mosquito buzzing around my ear. Finding out which things I can tolerate and which things I can't is a never-ending journey of pain and misery happiness.
In this post I'm really only focusing on a subset of stoicism, namely that of "Freedom is secured not by the fulfilling of men's desires, but by the removal of desire". It's quite difficult to believe this and yet be ambitious at the same time, at least for me. The best I can do is convince myself that the ambition part of my life is only just a game, because, since I am a stoic, it is something I could easily live without and therefore cannot place a very high value on losing it, because I can convince myself to be happy regardless of the outcome of my ambitions.
Fortunately, I am aware of this, so when I realize that my stoicism is causing me to miss chances in life, my conscious mind reminds me of it and I can try to self-correct. It takes a conscious effort though, in the same way that an introvert needs to spend conscious effort on socializing. It tends to be less prevalent when I'm tired or stressed out.
I've been this way since university. No matter what happens, my state-at-rest always returns to being a stoic. It's a very solid foundation for a life. Perhaps too solid. Thoughts?