What would you do if your partner hadn't proposed after nearly 3 years

[Theresalwaysmoneyinthebananastand]

Or even just said after 3 years that they wanted to marry you and were intending to get engaged soon.
Would you wait a bit longer or leave?
Assuming the partner is not 21 or something incredibly young

What does he say when you speak about it?

If you haven't spoken about it I wouldn't just wait unless you have prepared yourself for the inevitability that he has no intention of ever proposing.

Did you not talk about marriage?
Sorry, but if people can't talk about it I don't think they are mature enough for it. If you talked about it, what did he say? There is no need to sit on ones arse quietly and hope for proposal...
Communication. People should learn that otherwise their lives will be hell