It sounds like you really like her and you aren’t UNattracted to her, so I would give it another date or two to see how you feel. I mean, that’s the point of dating — to get to know someone, to weigh (no pun intended) potential pros and cons, and to gauge attraction level. Sometimes attraction hits you right off the bat. Sometimes it takes a little time to develop. And, sometimes, the person you thought was really hot turns out to be a cad and you aren’t so attracted anymore. At any rate, the pro column you describe sounds strong enough to at least give this a “fair start” as you say — another date or two — to see if you feel any chemistry, and to get a sense of whether this woman is serious about her desire to “be skinny like she used to be” and actively working on getting in shape. Even if she did lose weight, though, there’s no guarantee that she’ll keep it off. On the contrary, most people DO lose and gain weight over the course of their life. And, of course, people’s looks certainly change as they age. But if you can build a strong relationship on the foundation of love, respect, trust, chemistry, and initial attraction, all of that can generally carry you through the physical changes time will bring. But… yeah, if there’s no attraction to begin with, it will be hard to build the foundation you’ll need for a long and successful relationship. (Still: Give it one or two more dates before moving on. At least then you won’t have to wonder “what if.”)
No, and no. The only thing “denying” him will do is make him look elsewhere for what he can’t get from you and isn’t getting from the sugar mama. You can’t give him what his sugar mama can, and, unless he decides money and “going places” isn’t important to him, your gold-digger guy is always going to be on the hunt for someone who can provide that for him (as well as someone who can meet his sexual needs, even if that isn’t the same person).
If you have a relationship/dating question I can help answer, you can send me your letters at firstname.lastname@example.org.