Don't rely on your writing group's feedback alone - people are naturally kind, especially in group settings where everyone's invested in being supportive. What matters more is whether readers outside that circle are drawn to *specific* elements of your writing, not just whether they say it's good.
Here's something I haven't seen mentioned: track which sentences or passages get the strongest reactions across different readers, then analyze what they have in common. If three unrelated people all highlight the same paragraph for the same reason (the humor, the pacing, the way you described something), that's actual style emerging. If feedback is scattered - one person loves your dialogue, another says it's clunky, a third doesn't mention it - you're probably still finding your voice. Real style shows up as a pattern, not an accident.
Also, read your old stuff from year one and compare it to now. Not to judge it, but to spot what's genuinely changed versus what's just... always been there. If you notice you've stopped doing something because you realized it wasn't working, or you've started doing something deliberately because it serves your voice - that's development, not comfort. Comfort feels invisible. Real style feels intentional when you look back at it.