<human>: We've been together a year, and are both 22. He shows he loves me, not only through his words but his actions as well. All we do is lay in bed talking and holding each other. I know I love him with every part of me, but there's a coward in me that's dying to conquer the rational part of me.

I do not know why I became so doubtful of love. Maybe it's because I hear about more relationships failing than succeeding. I also can't stop thinking about how painful it would be if he were to break my heart. As it is, even when he is slightly angry with me about something, it colors every part of my world--I can't focus, I feel sick, all I want to do is cry, etc. I think I react so strongly because I truly and deeply love him.

The rational part of me knows what I am doing is ridiculous. I know that I am wasting precious time worrying about if things go wrong rather than just enjoying everything. 

So how do I snap out of it? These feelings come in waves, and are not always there. But when they are, I get this horrible sinking feeling I cant seem to shake.

Could you distill the essence of the text into 1-3 sentences?
<bot>: having trouble believing my boyfriend is sincere, even though he is a great boyfriend who loves me. How do I stop being such a coward?