Her Dirty Secret - The Safeguarded Heart Series, #4

A forbidden affair that's practically irresistible... Emily Hoyt is often referred to as a "free spirit, " but she knows that's just a nice way to say "flake." She doesn't normally let it bother her, but when her perfect big brother unexpectedly announces he's gotten married, Emily once again feels the pressure to be more than the meandering musician she is. Alessandro Giordano is the lying, selfish bastard Emily had pegged as bad news.
But when they meet at the engagement-turned-wedding celebration, they're both looking to escape, and the instant chemistry they have pushes them together. Is their attraction just a diversion, or could it really be more? Note: Though this is the fourth book in the series, it can be read as a standalone.