Most Helpful Girl
He went straight out to tell you: you need to change your way of thinking or you're going to lose this guy. Metaphorically speaking, you are drowning, but struggling and yelling so hard that no one can hold on to or get through to you, because you keep thrashing around. You know that scene in Harry Potter where Ron keeps yelling and struggling in that plant thing, but because Harry and Hermione calm down and relax, the plant lets them go? You are Ron right now.
So let me ask you: what is the WORST thing that could possibly happen to you?
1) Your boyfriend could dump you, because he feels smothered.
2) Your closest family members could die from a medical condition.
3) A younger sibling could commit suicide.
4) Your house could burn down.
5) Your family could go bankrupt.
6) You could get out into the real world and realize that you haven't worked hard enough in school, so the only jobs available are humbling and pay very little.
7) You could be severely injured in a car accident, so you'll never walk again.
8) You could have some kind of accident that severely deforms your face.
9) You could die, go to hell, and realize that your focus in life was completely off.
10) The list goes on.
A lot can happen in life, but the key is to focus on what's actually happening, continue to think and act rationally in spite of what's happening, and know that being logical DOES pay off.
Why does it matter so much if he's lying? That reflects more on his character than yours. Why does it matter if he's cheating? You could always find another boyfriend. Don't say "no, he's special, and no one would like me", because no matter how mean/ugly/stupid you are, there is always going to be someone who wants to date you. That's just a fact of life. Moreover, dating is a skill! You could learn how to do it better, practice, and be a natural at picking up guys...just like playing sports or doing math. Moreover, do you NEED to be in a relationship to be happy?
Life will go on whether you do or do not stay with this dude. He is not the be all and end all of your existence. You should never make ANYONE responsible for all the happiness in your life, regardless of if you're dating/married to them. YOU are responsible.
Don't worry about him leaving/cheating/lying, because hey: that is NOT the worst thing in the world. You need to find some new life passions that can turn into hobbies and enrich you. Read more books! Start with Dale Carnegie and C.S. Lewis. Do some math/science: nothing brings you back to earth quite as fast as doing math/science.