How do you know when you're in the right relationship?

^^^^ I agree, you never know You shouldn't even worried about that. If you don't know how long it will last, just enjoy what you have now :v

Well, alot of people would say many things. However in my opinion it's simple. Similar core values. You can both be completely different, but these are what's important. Like for instance, Honesty, Morality. Trust, what you both want in life. How you both deal with conflict. In my opinion that's the best 'sign'. However, people can lie, cheat, and do unforgivable things, that you never expected even after incredibly long periods of time. So you only know by taking a chance and take the jump.