Is the flame dying?

I (22F) have been dating my bf (22m) for almost two years now. We have basically had every talk know to man with one another. We know everything about each other and almost see each other every day. We have a great time every time as well, at least i think. Sometimes when are out together, I look at him and feel like I have made no difference in his life. Like there has been no positives changes in his life since being with me. While my life has gotten so much better, i’m not lonely anymore, i have some I can talk to every day, just all that. I’m worried that I don’t make a difference in his life, and I don’t want to bring it up since I feel like it might sound like complaining or something. Does anyone have some advice? This is my first relationship so I don’t know if relationships just plateau sometimes.