The study by the O’Leary team found there were 12 factors that lead to successful long-term relationships. Food for thought.
Thinking positively about your partner.
Thinking about your partner when apart.
Difficulty concentrating on other things when thinking about your partner.
Enjoying novel and challenging activities.
Spending time together.
Being turned on by your partner.
Engaging in sexual intercourse.
Feeling generally happy.
Wanting to know where your partner is at all times.
Obsessively thinking about your partner.
Having a strong passion for life.
O’Leary, K., Acevedo, B. P., Aron, A., Huddy, L., & Mashek, D. (2012). Is long-term love more than a rare phenomenon? If so, what are its correlates?. Social Psychological and Personality Science, 3(2), 241-249. doi:10.1177/1948550611417015
I think most of those 12 are categorical opposites of Dr. John Gottmans 4 Horsemen which he basically describes as:
The first horseman in a relationship is criticism
The second horseman is contempt
The third horseman is defensiveness
The fourth horseman is stonewalling
According to Gottman, the presence of any two is almost a sure sign of impending divorce while the presence of all 4 means the relationship is too far gone to repair. The exception is that if #'s 3 and 4 are the only two, often times a committed couple can work things out.