nos·tal·gia [no-stal-juh, -jee-uh, nuh-] a wistful desire to return in thought or in fact to a former time in one's life, to one's home or homeland, or to one's family and friends; a sentimental yearning for the happiness of a former place or time: a nostalgia for his college days.
Nostalgia can make us want to go back and live in days that have already past us by. Beware, nostalgia may give you a false sense that things were better when....you were in that other relationship, when you had that other job, before you moved out of your parents' house, etc. We tend to forget about the chain of events that made us.....get out of that relationship, get a new job, move out on our own, etc. When reminiscing, remember not to be nostalgic but realistic and most importantly, enjoy the moment you're in. The present is a gift and you will not be able do it over. If you're so stuck in the past that you cannot enjoy life today, maybe you need to make some changes so that you won't be so inclined to want to go backward.
Remember, change is good. Holding on to the past can potentially blocking blessings. Time never moves backward, always forward. And so should you....