This situation definitely sounds confusing, but it’s great that you’re seeking advice before jumping to conclusions. Here are a few things to consider and steps you might take:

1. Acknowledge Your Feelings

It’s completely normal to feel a little hurt or left out, especially when you’re used to including your girlfriend in your plans with friends. You might feel like the balance of effort wasn’t reciprocated, and that’s valid.

2. Consider Her Perspective

Your girlfriend might have had innocent reasons for wanting to go alone. Perhaps she wanted some uninterrupted time to catch up with old friends or thought you’d feel more comfortable staying back rather than being at a party. Her hesitation and phrasing, like "I don’t want to uninvite you," suggests she may have been worried about hurting your feelings but didn’t know how to communicate her preference directly.

3. Reflect on the Context

Think about how your relationship dynamics normally work. If this behavior is out of the ordinary for her, it might simply have been a one-off situation that doesn’t reflect anything deeper. However, if you’ve noticed other instances where you’ve felt excluded, that could warrant a more in-depth conversation.

4. Decide Whether to Bring It Up

If this still bothers you, it’s worth having a calm and open conversation with her. Keep the focus on how the situation made you feel rather than placing blame. For example:

"Hey, I wanted to talk about something that’s been on my mind since the holidays. When you asked if I’d stay back during your meetup with friends, I felt a little surprised and left out. I’m curious if there was a reason you preferred to go alone—I just want to understand."

This approach invites her to share her perspective without feeling defensive and allows you to express your feelings constructively.

5. Evaluate Future Expectations

Relationships involve understanding each other’s preferences and boundaries. If it’s important to you to always feel included in social plans, it’s okay to communicate that. Similarly, it’s also okay for her to sometimes want solo time with her friends. Finding a balance that respects both of your needs is key.

6. Let Go if It’s Not a Pattern

If this seems like an isolated incident and she otherwise includes you in her life, it may not be worth dwelling on. Everyone has moments where they navigate social dynamics imperfectly. A small misunderstanding like this doesn’t necessarily indicate a larger issue in your relationship.

Conclusion

Ultimately, clear communication is your best approach here. If you still feel uneasy, address it with her calmly and without judgment. If this is a rare occurrence and her intentions were good, letting it go after gaining clarity might be the best course of action. Relationships thrive on mutual understanding and trust, so framing your conversation with that in mind can only strengthen your bond.