<human>: Give me a shortened version of the text

Hi Reddit,

Using a throwaway for obvious reasons, your advice here would be awesome.

For the last few weeks I've been hanging out/partying with my this girl (Jill), who I've known for around a year now, but only really just started to get to know. Everything has been great and I've started to develop feelings for her, and I'm fairly certain they're mutual.

Here's the problem. My flatmate (Tom, there's 4 other people in this flat, we're all friends) dated Jill last year for around 6 months, with him ending the relationship (he may have cheated on her, I'm not sure, but he definitely ended it, not her). This was in September last year, so over 6 months ago. Tom's my friend, but we're not super close (we met through mutual friends of ours). I don't really want to lose him as a friend at this point, but if that's what it comes down to in the worst case then I could handle it. He's aware I've been out drinking and partying with Jill, and hasn't complained to me (or her, as far as I know). 

I really want to tell him I like her so that I'm not hiding anything from him, but I'm really concerned that he'll freak out. For what it's worth, his friends in the past have dated my exs (years ago though), and I never really had a problem with that.

What should I do? I'm thinking I sit him down and just tell him straight to his face that I'm interested in her. I feel I should at least tell him before doing anything, but I'm not really seeking his approval.
<bot>: Want to date flatmates ex, sure she's interested in me too, but not sure how to go about telling my flatmate.