Welcome Irina, this is mccoy from Italy. Re: pessimism vs optimism: i find my mood and mental perspective may swing a little but since I hate moods I do whatever I can to kill them. I find a good strategy is to dissociate from them and take as much mental attention as possible onto the Christ center, that helps.
Unfortunately, they tend to come, sometimes out of nowhere. It's a very good mental workout trying to overcome them.
We're all slaves of the flesh until we are able to overcome the karma of rebirth. Also, we may see it as mantaining the flesh, like we would do for a vehicle. So we would be mechanics, not slaves. Steve's truck is well mantained, otherwise he could be left stuck on the road. My car as well, I work with it and getting stuck would be a huge bummer. We become slaves when we overindulge in the whims of the flesh. A little pampering usually does not imply being a slave, but may be a psychological necessity. Often it's hard to tell a necessity from a mere indulgence and the ego takes advantage of it. Life wasn't meant to be easy. Important is to do one's best, and offer it to God.
End of the sermon, lol.
Maybe it's hard to tell a psychological necessity from a mere indulgence because we have indulged and created certain habits from one life to the next.