How do I tell a woman I can’t be with her because she’s much older than me and has kids gently?

I go to this bar somewhat often and got to talking to a woman who’s 37 and I’m 25. Lately, she’s been hitting on me and has now made it clear that she’s really into me and don’t get me wrong she’s attractive and has a really good personality but the age gap is too big and she already has kids. Other men usually hit on her often and the fact that she rejects them all but hits on me admittedly boosted my confidence and I would flirt back a little bit and now I’ve found myself in a situation where she’s wanting to be with me but I’d prefer us to just stay as friends. I’m not the type to hook up with women outside of a relationship and I can’t date her because the age difference and her already having kids. I don’t know how I can let her down with the reasonings above without hurting her feelings and hoping to maintain the friendship or things not be awkward in the least