Have Relationship Questions? Ask a Counselor for Answers ASAP
If you're asking about what qualities sustain a relationship, some of these are-
having more things in common and doing things that both of you enjoy, keeping an open communication (no secrets, listening to one another even if the other person is sharing something you do not agree with or find disturbing/sad), compromising/being flexible.
At times, it requires doing things for the other person not because it will make us feel good but doing it out of love and altruism (even if it means sacrifice of something in our own life)