In the future, with new clients, I would put in place an agreement of your terms for payment and cancellation. You have to decide what feels right and fair for you, and having such an agreement will only lend itself to your clients viewing you as highly professional, (increasing their expectation of success)!
I'd encourage you to revisit something you said in your original post, and consider shifting your point of view, just a little. (I hope you don't see this as splitting hairs, because in this field, we know that the words people choose are like windows, and they are not an accident) You said, "This is obviously frustrating as Im not moving forward with them..." I understand that you, professionally, are trying to move forward, and this is thwarted when your subjects aren't complying with what you need to have that happen. However, these subtle subconcious points may be being communicated to your client, and without either of you knowing it, contribute to their distancing... We need to be careful not to view our clients in terms of how they impact us, but rather, how we impact them. In the beginning, it can be hard, because with only a limited clientele, we want to really milk them for all the experience they can offer us. However, the truer our intention to help them is, the more they will effectively be helped by us, and this will in turn bring more clients via word of mouth from satisfied clients! So you may want to consider focusing consciously on how you are helping your clients move forward with you, rather than you moving forward with them. I hope you can appreciate and receive this subtle nuance, as it truly will impact the energy that you illicit. And there is power in this view. Clients will move forward at their own rate and pace, based on their personal journey of life. Some clients may battle with change, and sometimes they may waiver in terms of how much change they are really ready to welcome into their lives. If a client isn't ready and motivated to move forward, that's no reflection on you. You will continue to move forward professionally, while new clients come onto your calendar, ready to move forward with you. View yourself as moving forward, and helping your clients to move forward with you - rather than you moving forward with them (implying that if they aren't ready to work with you, you'll not progress). Know that you can and will help clients who are ready to receive what you have to offer them, and these others just may not be. Your professional success can not hinge upon 3 people. It's too much pressure on them, even if neither they, nor you, are consciously aware of it. Let your desire be for helping them move forward, and trust that they will do this at their rate and comfort level. You are moving forward. When you emit this, without contingency on what your clients are or are not doing in terms of their own momentum, you will naturally attract more and more. This will also make it easier for your clients to sense your own sincere desire to help them. It can be tricky to see our own success as a mere secondary gain of helping others, but when we can make this shift, people will pick up on our sincerity to help them, and our success will take off more effortlessly. Visualize a full calendar of clients, and when one happens to cancel for whatever reason, it's just a little extra breathing room on a busy day to catch up on some reading or place a phone call to a friend. :)