I just finished Calm My Anxious Heart by Linda Dillow and recommended to me by Catherine. This book is every bit as good as Catherine described, and I have followed suit in ordering a copy for myself, and actually another to give away.
Calm My Anxious Heart deals with the issue of contentment and trusting God with whatever circumstances He has allowed in your life. Some of the chapter titles include:
Content with Circumstances
Content to be Me
Content with my Role
Content in Relationships
Worry is Like a Rocking Chair
Trusting God with the What Ifs
Trusting God with the If Onlys
Trusting God with the Whys
It wasn't until I got to the middle of the book that I found what she was saying to be very applicable to my life right now. I had never really thought of contentment as the opposite of anxiousness or of worry.
This book is challenging and comforting all at the same time. Dillow is a very transparent and real writer and shares many lessons from her own life. I do highly recommend this book.