how to know if he's the one?

Unnie
I have been with my boyfriend for almost 5 years, we met in undergrad and stayed together after graduation. We both got good jobs and are on the right path to a successful future. He treats me very well. He's considerate, faithful, loving, kind, just overall an awesome person. He's not very romantic, but does small things like giving me a massage when i'm tired or surprising me with some yummy food and i love that about him. 
Now that we are in our mid 20s, we talk about marriage now and then. I love him very much and know i will be happy with him my whole life. But theres always that tiny thought in my head, is he the ONE? One driving factor is we are from different ethnicities and I worry about how people will look at us and if our children will be bullied. How did you ladies decide? Any event that made you realize that he/she must be the one?