Your posting online to find a friend is just going to lead you into the same cycle where your girlfriend dominates any social situation you’re a part of, even with your new friend/s. So, while getting a new friend online may make you feel better now, it’s not going to help in the long run.
Your problem is really between you and your girlfriend. And I think the answer is [i]compromise[/i].
You both have to work towards the middle a little more. In other words, she has to be conscious of how her behavior is affecting your feelings when you’re in public, and you have to be conscious of how your introversion is affecting your own feelings when you’re in public. She has to tone it down a little and you have to dial it up a little. See if you can both agree on that compromise, and then practice it out in public.
In addition, you can take responsibility for your part in your joint social life. For instance, she’ll probably only dominate the arena when she’s able to. If you’re at a party with lots of people, you don’t have to be at each others’ sides the entire time. You can wander off and start your own conversations with other people. Dinner parties often have couples interspersed with other people for variety. If you keep going out with the same crowd and keep getting the same patterns of behavior, then maybe augmenting your social life so that you go out with new people will help you find other extroverts ❗ as well as other people who are mostly interested in you.
This doesn’t have to be a deal breaker, but it does require some work from both of you. She can’t be obstinate and say, “That’s just the way I am,” because that’s not generous. And she may have said it because she felt backed into a corner. You can ask her, “If I try taking center stage more often, will you try backing off more often?” That will take BOTH of you out of your comfort zones and your normal social roles, and help you find some new ground that may be better for you both.
I hope that helps!
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