One website or Two?

I have two websites: one for my first book, No Longer Stuck, and the other for a nonprofit counseling organization, Helping Others Heal. I am struggling with which one to market. The goal is to market my books and resources for churches, through NoLongerStuck.com, and our Mental Health Coaching resources at HelpingOthersHeal.org.

I am trying to decide if I can use one site for both purposes. This would save me time and money, as I would not have to create and maintain two sites in addition to my personal site.

I’d especially like to hear from those who have done series on different topics, fiction or non-fiction. Did you market each separately?

Thanks for your input.