If you are considering getting serious (i.e. emotionally investing) with a single mother, when there are other girls who don't have kids, who don't have exes still in the picture, you probably have oneitis--if you're wondering about whether she'll come back even though she fvcked her ex and the father of her kids on vacation, you definitely have oneitis.
Oneitis is a state of mind, not based on physical reality. For instance, you could be trapped on an island with one girl for the rest of your life and never catch oneitis for her; or you could be in a modern city with millions of girls and even sleep with a new girl every night and still have oneitis for that 'one special girl.' Not a knock--happens to all of us from time to time. But you have to accept it before you can let it go. By resisting the notion you have oneitis, you're reinforcing you're oneitis in the inverse. Make sense?
Now onto the second problem: single mothers. Of course they're cool (til they have you hooked); they know that having a kid drops their RMV (relationship market value) 3 or more points and will be compelled to make up for it in other ways. They are also strictly on the market for a beta--unless you're strictly the hookup guy (which you might've been, but then you caught feelings). You can't have a longstanding relationship with this girl and be alpha--her hypergamy won't allow it; she needs male investment desperately. You probably didn't fit the bill all that well (good thing, really), but her ex dropped her and she had to find somebody ASAP. She doesn't have time to waste with you. But you let your ego get involved. Again, no shade; it happens. But you have to realize it.
You're 24. I don't care how awesome this girl is, give it a year or two and you'll realize the extent of the bullet you just judged. Went through a similar situation with a single mom when I was 19. Thank god she only saw me as a hot hookup (even though she promised a lot more than that)--my bluepill ass was ready to jeopardize my future for that girl. When she dropped me for a provider, I was devastated. I felt emasculated and helpless. It was only four or fi e years later when she started hitting me up trying to hookup when she was in town (even though she's engaged to her provider/proxy father to her child) that I realized I won that game in a big way.
Now for advice. Block her number; delete her from social media--for your sake. If, after a year, you still think it's a good idea to get re-involved with this girl, go for it.