There is no such thing as luck. Yes, maybe 1 out of a million can win a lottery or get a promotion, but these are just a very few people.
If you want to have success in love with your partner, then you both need to work hard together on it, otherwise it won’t last. Learn to listen to each other and try to understand what the other person is saying. You need to talk and find the solution. Trust blindly, because this person has never lied to you. A beautiful relationship can last as long as both people want it. Otherwise I don’t see the point of staying together and pretending that everything is fine.
It’s the same with friendship. It can last only if both people want it and keep it going. People can move to another city or country and still be friends even though thousands of miles apart. Some can’t be friends even if they live across the street from each other. Why? Because they don’t want to. Maybe they already have their circle of friends and don’t feel like they need more.