Bunny has started becoming aggressive

We have had are Female French Lop -Bunny- for around 6 months now, she got spayed about a month ago as we were looking to buy another rabbit to keep her company, so far Bunny hasnt liked the new rabbit -Luna- so we have decided to keep them seperate. For around about the past week Bunny has been very aggressive towards my Boyfriend, she has but him once and drew blood and attempted to bite him on several occasions (Once when he was feeding her) I don't know what could be wrong? We thought it was Luna's scent on him that was causing the problem but Bunny is fine with me and will even let me in her pen to stroke her and clean her out, but when my boyfriend goes in she lunges. He has even went in to her before he was went near Luna. Any advice on what might be wrong would be appreciated as I am going away for a few days and I cant have Bunny attacking him every time he goes near her to feed her!

Thanks!

She may still be quite hormonal - it's not been long since she was spayed. Give her another month or two.
She may be showing referred aggression from the presence of another rabbit that she can see / smell.
She may be defending her space - how much room does she have? Often giving them extra space makes them less defensive.
Does she see your boyfriend as a threat if he 'invades' her space - maybe in a different way to you? Maybe he could go armed with some really nice eg dandelion leaves (and gardening gloves), or shoo / bribe her into a carrier while he carries out the essentials as a short-term measure while you are away.

You won't resolve a behaviour problem in a couple of days so it will be a case of him avoiding putting himself in a position for her to attack. It's likely that the new bun has upset her confidence and it may be that your boyfriend just interacts with her slightly differently and it's enough to trigger the aggression - it could be as simple as you announce your presence by saying hello and he catches her off guard by being quieter.

Avoiding the situation also stops it becoming a habit. So he might call her to the run before going in the hutch or put some food down the opposite end before lifting out her food bowl. Put her in a carrier before cleaning out etc.

This covers aggression in more detail: http://www.therabbithouse.com/behaviour/problem-aggressive-rabbit.asp