Is it the actual funeral you are conducting or the choir?
If the latter you should hopefully be able to detach yourself from your own emotions and focus on the music.
However, it is important to remember the people who matter most at a funeral- the bereaved- and those who have a professional role to fulfil have to be able to subjugate their own feelings so as to give 100% to the event. I remember many years ago a clergy friend unwisely insisted on conducting his wife’s funeral, saying he felt it his duty as a husband and a priest.
Poor man, he barely got beyond the second sentence when he broke down and his curate had to take over. We all felt for him but also that he should not even have attempted it. We are all only human.
I am sure you will make the right decision and that you will rise to the occasion, letting the music carry you through.