Annie's Baby by Beatrice Sparks

When Annie discovers she's pregnant by her boyfriend, she's devastated. She has never felt so alone. With no one she can talk to, she pours her heart out to her diary, confiding her feelings of panic, self-doubt, and the desperate hope that some day she can turn her life around. She decides she wants to keep her baby and dreams of loving and caring for this little person. But after the baby is born, it's in her diary that she faces the agonizing question: Can she really raise this child on her own?