It seems that eudaimonia isn't just a fleeting emotion of giddiness that arises when you get something that you want, but instead it is an expansive sense of fulfillment and completeness.
Yes, you must be correct. I think "well-being" has most of the same sense -- it is our deeply internal and long-enduring sense of well-being. Of course, we can easily see how well-being is closely connected with the pleasure of being alive.