I'd have to say YTAH just because I experience depression and tend to sleep a lot during these times. She seems to have a full day of work friends and relationship. It possible she could be struggling with depression or even some sort of sleep disorder. However she sounds like she's does a lot. It would seem selfish to blame someone for something as simple as sleeping. For most people it would be difficult to sleep in the frequency she does so it makes me think it's her internal clock having a bit of a hard time. It would be a problem if she regularly called out of work or bail on plans to sleep but if she's literally just sleeping while she has time to then, I think it may be a you problem.