I read your concerns , first I would like to say is that no one should be held responsible for another person's happiness.
I would think in a perfect world we would all compliment each other , sad to say but with so much baggage we bring into relationships it no wonder we all have issues that cause problems . I suggest you find a couple who may be older but that's not necessary have a perfect relationships and ask them how they have made Thier relationship work.
Two are better than one.
My wife and I purchased iPhones and we communicate with one another in tips on how to use them ,lol.
Find something that both can help each other with and let him know he is your hero . I know that sounds dorky but if you would try this and see how it works as a man I know when my wife makes me feel that I can fix anything with her words .
Now another thing choose your battle something's are not worth the trouble .
It will not cause you to loose your life if by some chance he is cheating .
There is an clip of Media giving council to a young man about relationships gone bad .
YouTube clip some one sent me in face book.
It's worth watching.
Life is to short to be unhappy please don't be dependent on another person to make you complete . We live in a broken world and we all are very short .