It's crucial that they hold each other in high regard, that they often believe in each other more than they believe in themselves, and that they trust what their partner does. Therefore, never involve a third party in any of your relationships to try to resolve minor problems and misunderstandings. In my experience, the best relationships form naturally, so finding ways to go out and socialize, meet new people and form connections that don't have the pressure of a first date is where I've found my most meaningful romantic relationships. Just as causing pain to the muscles allows them to grow stronger again, introducing some pain into the relationship through vulnerability strengthens the relationship. When you're in a relationship and you've successfully overcome challenges, you've overcome communication problems, and you've found the perfect balance between being independent and being part of a team, it's easy to think that you have everything related to the relationship.
In fact, there are some common things that people in a relationship do wrong when trying to give love advice to their single friends. I could give you a lot of advice here with similar examples, but I am a firm believer that sometimes advice is effective and sometimes it's not. Dating and relationship advice tends to be clichéd (“There are lots of fish in the sea”) or too specific for the person sharing it (what worked for them won't necessarily work for you). When I got married almost three years ago, at the wedding reception I asked some of the older and wiser people in attendance to give me some advice from their own relationships to make sure my wife and I didn't shit in (the same) bed.
