<human>: Give me a shortened version of the text

I [20F] have been in a relationship with my boyfriend [21M] for ten months now.  This is my first romantic relationship of any type or length.  We're really happy with where we are right now, and we're stable, and a breakup is definitely NOT imminent.  I love him and he is a hugely important part of my life.  

Even though our relationship is going well, I get freaked out over the mere possibility of breaking up with him.  We might end up getting married.  Or we might break up.  We're young and these things happen; I get that.  But sometimes, when the thought crosses my mind that I might have to lose him someday, I have a hard time dealing with it.  In a few cases, I've even gotten choked up and turned myself into a mess because the thought was just too much for me.  I'm kinda getting there now as I type this.  Sometimes I have to skip breakup songs because all I can think about is how much it would hurt to lose him.

Rationally, I know that if I ever had to break up with him, I'd get over it.  I'd move on with my life somehow.  Irrationally, though, I'm terrified of this possibility.  I'm also afraid that this fear will get so bad that I won't be able to "let him in" emotionally because I'll want to shield myself from potential pain.  

I know that I can't continue this train of thought, because it doesn't seem healthy, both for me and for the relationship.  But I'm just so scared and it bothers me because I can't get the thought out of my head.  Is this normal?  Is it because this is my first relationship?  What can I do about this?
<bot>: My boyfriend and I have a healthy, stable relationship, yet I freak out and get choked up at the mere thought that it might not last and I might have to break up with him someday.  How do I deal with this?