An example: in Colombia, when demonstrating the height of a child, you hold your hand vertically, while when talking about the height of an animal, you hold your hand horizontally. If you do the wrong thing, people may assume you're a foreigner and don't know, or they may assume you're just rude. The fact that I learned to hold my hand a certain way when speaking Spanish with Colombians doesn't mean my personality has changed, it means I've absorbed a cultural lesson and if I do it, I do it because I am trying to fit in.
The same things goes for the way in which you express yourself with speech. The way you greet people, how long you make small talk before "getting down to business", how to flirt in a bar; all of these things vary a LOT from country to country and if you want to fit in, then you need to pay attention and learn some things. But again, doing that does not mean that your personality has changed; you're just behaving differently.
One more thing - as somebody who studied theoretical linguistics and speaks the two languages fluently, any time people start making ridiculously subjective claims about a language like "English, a more unemotional and efficient language than Spanish" - keep in mind you're reading complete bullshit.
That's like saying the firewire cable that you use to transfer movies from your video camera is more "artistic" than the USB cable you use to attach your hard drive to your computer. It's confusing the signal with the carrier, and making some pretty subjective claims about the signal too.