I am a new employee and I have a co worker who recently started shunning me in the break room. I walk in and she acts very quiet. This is not a problem in itself. However when other employees who are friendly with me walk in, she starts to converse with them. I joke around too however the awkward silences are becoming hard to deal with. They only do this when she is around. When she leaves they start talking to me and laughing with me like normal. How should I confront her without appearing as if I am being aggressive towards her?
Be careful. Don't mistake work for a social club. It is not. You're there to make the company productive, not to make friends. Concentrate on being the best employee you can be rather than the most popular with a woman.
On the other hand, if you suspect you have an offensive behavior, seek out your manager's advice or the advice of HR. Explain to them that you noticed that an employee is not responding to you very well. You're concerned that you may have a personality trait that is not conducive to work. Ask if there is anything you should be doing to get along better with your co-workers.
Women get harassed at work on a regular basis. Be careful you're not being misinterpreted as someone that is striking up a workplace romance. Be professional. Avoid dating co-workers or even giving the impression that you'd like to date them. Focus on being productive.