How to be roomates with my ex he already moved on I haven't?

[Anonymous]

Our lease dosent end until January im saving up so i can get my own place a few days ago he told me he think we should just be friends and he's been thinking about this for a while now. I agreed but last night we had sex so I thought he changed his mind about just wanting to be friends and he's been being extra nice to me. but today he kept getting text messages from someone and said "just keep complaining ill be back" he still has not come back it's almost 1 o'clock. I think he's with another female why would he sleep with me if he's moved on to someone else and how can I ignore my feelings for him and just be his roomate

[JakeS00]

It's an ex though right? Why would you worry if he's with another female? Is that what I'm getting at?