<human>: Can you summarize the given text in a few sentences?

I don't have a lot of experience with relationships so I'm not really sure how to handle this or how to feel.

I started talking to him in the beginning of March (one month to this day exactly). We really started hitting it off and he and I are actually really similar and comfortable around each other.

I guess we both knew that we liked each other but aren't officially dating. And today he dropped a truth bomb on me and the gist of it was, "I've been dating someone for a while now and we hit a rough patch and now I definitely know that I'm going to break it off once the week ends. I didn't want to give off the impression that I'm being deceptive or cheating on you."

I don't know how to feel, because on one hand, I appreciate him for being honest and telling me the truth about the situation, but on the other hand, it's left me with a bad taste in my mouth because if I knew that he was dating someone already, I wouldn't have pursued him and flirted with him (and him flirting back). I feel like it's disrespectful for him to treat both of us girls like that, even if he was going through a rough patch with his girlfriend.

I want to say something about it and tell him my feelings, but I'm a really non-confrontational person and I don't want it to make it sound like I'm attacking him. But. It's just left me with a slight sinking feeling in my stomach. I don't want to be a rebound. I don't want to be that girl. How do I know if he really, genuinely likes me or only likes me as a rebound, because he constantly tells me that he's never been this comfortable with another person before and he highly values the relationship that we have.

Again, I don't know how to deal with this because I've only been in 2 other relationships spread out in a span of 3 and a half years.

Any advice is helpful. Thank you all.
<bot>: Boy I like confessed that he was still dating another person when we started liking each other and I don't know how to act or what to feel.