Question for Coaches

I think you are still underestimating the importance of the WR position. You are involved in every play of the offense, whether or not the ball is being thrown or not. Stalk blocking corners, cracking down on strong safeties or outside backers, running routes, finding seams in zones, catching the ball. It seems from what you're saying is that your looking for a position with less pressure than free safety, which I will admit carrys a lot of responsibility with it to "never let anyone get behind you", while the coaches still expect you to play run support! I don't think wide receiver is a lower pressure position, there are a lot of important responsibilities for the player at that position. The only break you really get is a lot of teams use the WR to run plays into the huddle, so you only play every other play.
Like you stated in your first posting, you need to improve your ability to let your mistakes go during the game. The beauty of football to a lot of people is it is the ultimate team game. Every player on field, offense and defense, has a responsibility. O line blocks, they may be base, pulling, pass blocking, reading blitzs, no relaxing there. Backs and receivers block, carry the football, go out on passes, and have to be in specific locations on the field in every play. D line and backers have gap responsibilities, need to modify these with stunts and blitzs, and secondary has pass coverage, and secondary run support.
There is no position you can play without having responsibility for the success of your football team. One player can not win or lose a game all by himself on one play. That is what you need to realize in order to let past mistakes go. Strive to learn from your mistakes, but don't dwell on them. You can't change them, but you can be better prepared to not let mistakes reoccur. Think about those long pass plays for a second. Did the DE or OLB hold up the receivers at the line of scrimmage, did the cornerbacks communicate with the safeties during the play, letting you know they were releasing the receiver deep? You do not have total responsibility for everything happening on the field, just your job. You have to trust that your teammates are doing their jobs at the same time you do yours. If you are set on the WR position, by all means you should do everything in your ability to do so. However, don't assume that because you made a mistake on one play in one game that you are incapable of playing free safety. Lots of players play both offense and defense, especially at the high school level. Whatever you decide, try to learn what is expected of you on every play, and execute your responsibilities to the best of your ability. That's all any coach can ask for. Good luck!