Inspired by this story.
Allegedly, there are three people involved: Alice, Bob, and Carol. Alice and Bob are married and they co-own a house (which is presumably in the UK). Their marriage is having issues, and they're in the process of divorce, although they both still stay in the house. One day Bob brings Carol to the house apparently for a one-night stand. Alice is livid, arguing that it is disrespectful. Bob counters that he owns 50% of the house, so he can do whatever he wants without Alice's consent.
Can Alice legally eject Carol from the house? Put alternatively, can Bob legally force Alice to accept Carol's presence in the house?