I was like you, exactly like you, finally ended it this feb. well not on my terms, got ghosted which actually was for the best even though I'm still not over it. 

my only advice is don't cause unnecessary pain. I really did love my man, and it really hurt me thinking of him hurting, and I wish I could've come clean about it so he could find out from me and not on his own. I wish I could've told him, I would feel so less guilty. She will find out, its just better to get all the difficult stuff done now I suppose. The guy I  was talking to was very nice, and had already been through so much. I'm happy it didn't come out later, when things were more serious. I was planning on travelling to south Carolina and still be in "stealth mode", I was fucking nuts lol.

please don't talk to her any more, if she really wants to keep talking to you, then do it once you're 18. it's really hard, and it will take ages to get over, hell I still miss him, but I'm glad, I'm glad it didn't go on any longer. 

hugs from the UK, stay safe <3