Losing trades are all part and parcel of a winning strategy, its impossible to win every trade, anybody who says they do are lying. I don't let the emotion of a losing trade get in my mind, I move onto the next trade. I'm not a glory hunter,looking to make hundreds of pips, each trade is ££'s, so I get in, grab a few pips and get out fairly quickly.
One thing stuck in my mind from many years ago, was a "story" by John Carter of CME, it goes something like this:
Imagine your a bird sat in a tree above a garden, surrounded by bushes, on the floor are the seeds you want to eat, but in the bushes are the cats wanting to eat you. Every now and again a window of opportunity appears for you to fly down, grab a few bits of seed before the cats know your there and safely return to your branch. The birds that get daring, stayed on the ground a bit longer, but never had the opportunity to return to the safety of the trees.
Using that analogy, I enter the market for a few scraps of points on a regular basis, in and out, take the pips, accept the losses, but never allow myself to stay in the markets long enough to lose out completely.