For starters let’s agree that there is no such thing as the “One”. Thank goodness there are many thousands of beings who we would each be well-suited for (insert all single people’s collective sigh of relief). What we are looking for in another we should also possess in ourselves: the maturity to commit, the willingness to own our relationship triggers and the ability to work on them when they arise. This is the basic formulation for a successful relationship. Then of course we all have preferences and it’s nice when our partners can compliment them emotionally, sexually and materially. Do they like to travel? Are they planning for children? Where do they wish to live? Do they enjoy our kinks? Finally (and this is a personal preference) are you excited to see them after a long day and do they still give you butterflies? While relationships don't necessarily require passion for a healthy partnership, I would rather sacrifice companionship for the possibility. Long-term relationships are not for the feint at heart. Love hard and love well.