I did not love the couple who showed me the first steps into the lifestyle, and helped me a HUGE lot with always being there for me and my 1,000 questions *lol*, but I liked them very well and found them both attractive.
It is not necessary to love your play partner to have strong sensual experiences.

However, when I found it was the thing for me, I went looking for a partner of my own for a real relationship. With love, it is just so much the better. I only can give myself truly if I love the other person. Plus, the fact that I love and trust him made me do a lot of things for him (and myself), that I would not have considered at all with a casual play partner.