Major breakup, 23m 24f

I know the title sounds like an oxymoron, but hear me out. I’ll preface this post with background information and pose my question at the end.

Me and my GF have been dating for 10 years and we’ve lived together for the past 5 years- 3 years in apartments and the past 2 years in a house I bought. All that to say we have a very mature relationship for our age. We’ve been through tremendous ups and downs together- not just relationship wise but just with life as well. We’ve been together for so long she just feels like a part of my life.

The problem is we’ve had major reoccurring conflicts over the past couple years regarding her behavior, I dont feel like I need to get into specifics, but it’s something she promises to change but never does. This cycle has worn down my love for her and for our relationship and I’m ready to end it- both for that reason and because I’ve recently felt a strong urge to want to experience dating again, as I’m still young and I don’t think I can even settle down at this point. (This is a new urge that I’m not even sure is related to the reoccurring issue)

My question is this: How do I break it to her? Obviously “just tell her”, but this feels like dropping a bomb on someone. Looking for advice from others who’ve shared this “burden”. How can I make it not soul crushing for her? I know this will blind side her to an extent. Would it be insulting to offer to remain friends?

Thanks in advance.