A client isn't falling in love with you, he's in love with his perception of you. It's a huge difference. Also, in love with you? Really? I think anyone who falls in love so easily, particularly in this kind of transactional situation, has no real idea of love. Instead, it's more a kind of obsession/infatuation.
If I were to ever find myself in this situation, I would cut ties. It's not part of the service (or the plan for that matter).
As for falling in love with a client? No, because again, it's not real. I'm only seeing him in a very controlled situation, he's on his best behaviour and I am being my best self. No matter how much I think we connect and get on, it's not authentic. However, I do consider a few of my clients as very dear friends and I genuinely love our time together. But do I want more? No.
If I were ever to find myself developing feelings for a client, I would cut ties and run a mile. It's so not what I want or what I am looking for either. This isn't Pretty Woman.