It depends I guess on how well you can compartmentalize. I've found the more emotionally draining dreams, or the ones that have a stronger impact in dream can cross over more easily. I'm on my third set, and some days are easier than others. I just happen to be the type who is live each day as your last and live let live so I tend to have an easier time it seems of brushing it off.
At the end of the day from what I've seen though, it comes down to who you are personally on how easy it can be to deal with things that happen.