well, having a personal plan for your life ensures you have boundries and a goal. this in turn, gives you some form of wall to hold yourself up against. if you had a plan you could have a reason to refuse engaging with certain people, and even have the ability to reason with yourself how a bad decision could potentially ruin something good for you. as for relationships, having goals could be good for both people, as there is a support system and the friends/significant other/ family member, would be able to help you along the way and if they are unsupportive, it gives you a better reason to come to terms of cutting off negetive influences. as for diet and nutrition, living a healthy lifestyle is very important to a good self-esteem, and having this is very necessary for having goals and living up to them, as with this self-esteem, you can have the personal strength to go on and accomplish your goals. hope this helps :)