So to paraphrase Mike Tyson and relate it back to betting:"Everyone's got a plan
. Until raceday".
You must expect to get hit because it happens to everyone, even the most successful punters that have ever lived. Be very clear on how you're going to deal with a losing run before it occurs so that when it happens you fully prepared both psychologically and in terms of sticking to your plan. This preparation and mindset is the only way you will be able to maintain discipline during the adrenaline rush that is raceday.