My (online) friend has been lying about their age

[FONT=""][COLOR=""][SIZE=""]TL;DR:
I thought my friend was 19, but is actually 23. I need help on how to confront them about it. I don't plan on being friends with them anymore, I just want to give them closure because we've been friends for 3 years(I don't want them to wonder about why I would suddenly ghost them.)

Context:
3 years ago I was in an online friend group, I was 13. We were all teenagers, I first met my friend(gonna call them Fire), they had told the group they were 17, but because I was in a group with a couple of other teenagers I wasn't too uncomfortable. Basically the friend group fell apart, and I remained friends with Fire. We've been friends for 3 years, and they have told me they were 17 still. I found out they were 23 from an account on one of their other social medias. I am really uncomfortable, because they were 20 when I was 13. How do I confront them and give them closure?

(note: they have never ever done anything inappropriate with me, we are just friends)[/size][/color][/font]

[Rivière]

Firstly, have you actually asked them why they lied about their age? Are you completely sure that the age they posted on another site isn't the age they've lied about and were truthful with you the whole time? Can you confirm which is the lie and which is really the truth?

I think rather than making assumptions, actually spend time with some probing questions to find out more before jumping the gun and making the assumption they've lied to you without proper evidence. The fact you're ready to drop them as your friend without actually giving them the chance to explain themselves is a little saddening. You may be surprised as to what their response is, if you give them the chance.

As you've said, they've never done anything inappropriate with you. You've developed a good 3-year friendship. Why throw it all away based on insufficient evidence and assumptions?

Talk to your friend and find out what's going on.