First off, I'm a rather solitary introvert. I don't get along too well with people, I don't enjoy conversing much (am pretty bad at it to be honest), I usually prefer to be alone. My boyfriend on the other hand is quite outgoing, has quite a few friends, talkative when he wants to be. We're pretty opposite when it come to this.
Lately it's been bothering me, this difference. He has friends that he will go out with, he'll bring me along sometimes too. He doesn't mind it, I don't mind it, his friends are pretty nice, at least around me. In turn, I don't really have anyone besides my sister really. I never minded this til recently. We've been together, 5 years this anniversary and it has never bothered me til recently.
I can't really put a finger on it as to why it is bothering me so much. Don't get me wrong, I don't crave socializing with other people, I don't crave the company of other people. I'm perfectly happy being alone or with him. For some reason, I've been feeling like there is an imbalance here and it will turn things sour. It's not even jealousy on my part, at least I don't think. It's been upsetting me, I can't even figure out why myself.
Lots of relationships sooner or later come to an end (or a change in their nature) for one reason or another; especially relationships between people as young as you are. Obsessing over your scary fantasies about what might happen someday can be self-fulfilling, but you don't have to live in them now. They are, after all, just fantasies. Focus on enjoying what you've got, deepening and building on it. Want to tell me (or just tell yourself) six things you especially love about your relationship, that make you feel good or give you confidence?
Does it bother you when your with him and other people? Or when you're alone later, just thinking about it? If the former, try to identify (name) the uncomfortable feeling/s in the moment when it's happening. If the latter, maybe you're just tormenting yourself with a non-problem.
Differences between people can often be complementary rather than conflictual. If you're concerned it might become an issue between you, ask him how he feels about it.
I think I'm a little scared that in the future, he will eventually see me as something that's just always "there" or around like a chore. Our relationship has lasted a lot longer than most our age so I am absolutely terrified he will get bored of me one day though I'm not sure if this has anything to do with the "uncomfortable" feeling.
It's definitely the latter. I've talked to him about it, he doesn't see any problem with it. In his eyes, he prefers my company to others and enjoys bringing me along. Obviously, this makes me quite happy, but on the other hand I feel that "uncomfortable" feeling. You're right though, I am tormenting myself with a non-problem.
Can you remember an incident when you were in the company of his friends and someone gave you a weird vibe? You may have picked it up subconsciously and that may be what's bothering you.