I'm not a love expert but I've been in that position before. In the end I needed clarity because in order to move on you need closure. Confess to her one last time ask her how she feels and then decide how to go on with yiur friendship after. If she really is worth being a long time friend, she'll still be your friend even if you have those feelings. I've confessed to my friend whom I have a relationship similar to yours and now we're still very very close friends. We even joke about the days when I liked her. We also push eachother to do our best finding our own partners. So yea closure might be your best bet. Goodluck mah dude.

This is not related to the manga but guys I need some advice.
There's a girl that I liked for 3 years, She's always in my mind, everything I do reminds me of her, one time I've gathered the courage to message her atleast(not to confess just chitchat so we can know each other better). She replied, our chitchats became often since then but sometimes we are not chatting for 1 week or worst 1-2 months, I don't like risking the friendship I built on those time so I'm not trying to annoy her by messaging her when I know she don't wanna talk to me, I'm still keeping these feelings by myself but tho it hurts one time before she told me about her crush, I just pretend that it doesn't effect me, sometime passed we're still in touch playing mobile games, I've asked her if she's playing MLBB but she said she doesn't, I've asked her if she wanted to play with me, since then we play together but I usually play MLBB in PC, and I have some mates who plays with me, we played with them then but tho it's painful that the way she's laughing at my jokes before is how she laugh at my playmates jokes and now she doesn't even bother to react when I joke, I was thinking of confessing to her but I couldn't, I got rejected by her before I could even confess she said "No courting, courting ain't allowed" we were sending VM that time when her father asked her why she wouldn't let me court in their place then she said that, IDC if you'll call me lame but I'm actually crying while writing this, I know my flaws, and that's what keeping me away from confessing, what should I do?