He introduces other girls to his friends but not me

If he's introducing casual dates to his crew but you've been exclusive for months and stay hidden, that's not random timing. He's had plenty of opportunity. What this usually signals is that he sees you as temporary, or he's unsure about the relationship and doesn't want to complicate things by making it official socially. Sometimes it's about him not being ready to answer questions from friends, which is its own red flag. The important part: this pattern tells you something about his intentions, not about your worth. Don't reframe it as something you need to fix by being cooler or less needy.

Before you bring this up directly, invite him to something social where his friends will be. Suggest a group dinner, a party, a casual hangout. See if he suddenly has reasons not to go, or if he goes but acts weird around you, or if he actually shows up and introduces you naturally. This tells you whether the barrier is real resistance or just inertia. If he dodges every group invite, you have your answer. If he goes and acts normal, then it's worth asking what the deal is. You gather facts first so the conversation isn't hypothetical.

When you do address it, frame it as confusion rather than accusation. Something like 'I've noticed you don't really include me when you see your friends. Is that a thing, or am I reading into it?' This opens the door for him to explain without making him defensive. Listen for the actual reason. Is it 'I'm not sure where this is going'? That's honest and actionable. Is it 'I don't want to make a big deal'? That's evasion. After he answers, tell him what you need. 'I'm at a point where I need to know if this is moving toward something real.' Then wait for him to step up or step back. Don't fill the silence. Don't negotiate. This is where you find out if he's in or out.