Well, some people aren't ready for a complete commitment, and it can be scary if you're feeling "pressured" in to it. I don't know your age, but there's most likely a long time ahead of you and many more things you want to see and do. Stress is a big thing and figuring out exactly what's stressing you and how to relieve it is never easy. You really need to sit down with yourself and figure out whether this relationship is still right for you.
People change as they get older, and that's natural... sometimes those changes make people drift apart, and sometimes you can't be sure if what you're doing today will ultimately lead to what you want from the future.
While I know you don't want to hurt anyone, I think you would be hurting everyone else MORE if you stayed in a relationship you weren't comfortable or happy with. While it may be hard, if YOU feel that this is what you need to do, then that's all there is too it.
But the call is yours... because for me? I'm feeling very similar, but I also know that I would like my future to continue this way. Sometimes the fear and stress build up on me, and I always wonder if I'm making the right decisions. At first, I was worried... I thought that my actions and stress were all because I was uninterested in the relationship... with time, I started realizing that it wasn't relationship based at all... if anything, my boyfriend was a large support in helping me with the stress.
Even when he wouldn't be there, suddenly those moods would set in, or even when I'm just sitting at home, and doing a puzzle, the mood will set in... and for me, I've come to realize that these aren't caused by my relationship, but only by the other things going on at the time. Does my relationship add a bit of stress? Of course... now I have one other person that I worry about. But is that the main cause? Definitely not.
The fear... it may always be there. I always wonder whether or not it will last, and I always question if this is right for me... but then? My boyfriend says or does something that makes me realize why I'm still with him, and just how truly happy he can make me. It's those moments that dictate my relationship, and not the random moodiness caused my all the world's stresses.
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Now, that's my person opinion... but it took me a while to realize. Sometimes I STILL doubt and wonder if I'm not just trying to make excuses... but then, like I said, something happens just to remind me how much I truly do care and how if this IS the last person I'm with, I can truly be content with that.
So thin kabout it... it's up to you. There's ALWAYS pressure in life, and sometimes it's hard to realize where it's coming from. Has there been a recent change in your lifestyle that may be making you anxious? Because one little thing can make all the other things seem much larger.. if that makes sense.
Either way, I can't help YOU sort out your thoughts... that's up to you. Talking to your boyfriend about certain things, may also help you realize how YOU are feeling, and what YOU want to do with it. It takes time but at the end of the day, if you need a change, you need a change... who knows what you'll decide, but just make sure that you DON'T let your fear or guilt of making your boyfriend or his family upset sway the way you make your decisions. This is about you and your happiness... and if you aren't happy with him, it will ultimately start showing up, and there will be many more problems that will make both of you unhappy, in my opinion.