Losing flips and bad beats happen, it is just part of the game, regardless of it's frequency. Getting in bad though, might be part of frustration. If I'm making correct calls and not winning, I'll keep going. Making questionable calls or getting in bad is whole different matter.
I'll spend time going through hand history to look for those flips if they could be avoided and analysis those bad calls to see why those were made. Long bouts of variance can be tough and hard to handle. Coming to grips without getting to emotional will determine the direction it takes you. More you go through it, easier to accept as being part of the game. It is that way with all long term poker players, regardless of the skill level.