Last Minute Fiancé by Carrie Ann Ryan

A single drunken night changed everything.
One positive test later, and I’m not only pregnant with my best friend’s baby, but I’m falling for him too.
Except when my ex finds out at work, I do the worst thing I could at that moment: I lie.
I make up a fake fiancé and my boss overhears.
Now I need my best friend to play the part. He’s good at it, too, since we can’t keep our hands off each other.
When we’re both forced to lean on each other, we’ll have to face facts.
There’s nothing fake about this relationship.
Even if I’ll break my heart in the process.