I find that telling the T in advance about a topic I want to discuss in the next session is very efficient -- sounds like you have already done that on the phone. I usually do this via email between sessions or mention at the end of a session what I would like to talk about next time. I've always stuck with the agenda so far and we always had good discussions about whatever I brought up this way. Then when I go to the session, just sit down and start straight and very directly. We dealt with sexual thoughts this way as well, even though for me those are far from stuff I feel very uncomfortable about and mine were not really romantic more purely sexual and I did not have them many times about the T.

I think the idea of making some written notes is good -- this is what I do in my between sessions emails in a way and then just open my "mental notes" when it's time in session and let the conversation flow freely. If you are feeling uncomfortable in the moment, perhaps telling the T just that (it's also part of your feelings) may not be bad either to make the T aware and give them an opportunity to help you through it. I think even the mere fact of which feelings and topics make us uncomfortable can be informative in therapy, information about how our minds and emotions work.