I want to go to graduate school in mathematics, completed my undergraduate degree in mathematics with 3.6/4 gpa (11 graduate level courses in maths and related courses, only 3 were A- rest A, 25+ courses in mathematics). I took way too many courses every semester (about 6) and got bad grade in one or two classes usually, which resulted in my gpa. To compensate this I did my masters, got 3.97/4 gpa with 9 classes (only one A-). However, I was not given a thesis question, the only thing that I had was that my advisor told me a result he found in X, and I should try to expand that to Y and Z. The extensions were trivial, and then he told me to find application for it. Everything I could think of were completely trivial, so I ended with potentially a subpar thesis (everywhere that I applied in Europe rejected my application after giving a short presentation on this thesis so I'm almost surely positive that it is a really bad thesis).
I've spent majority of my research experience (about 3-4) years with one professor and nothing came out of it aside from the minor extensions that I've mentioned above. I think the letter of recommendation he gave to me early in my education was "strong" (one professor in Europe told me this) but after getting rejected from all the PhD programs that I've applied to I got emotional and to certain degree might've burned the bridge (does not seem to return to my emails anymore) unintentionally by "hurting" his feeling that the projects doesn't seem to get anywhere and overstudied. So I'm not sure if I can get a good recommendation letter from him anymore, and I don't think there are others that can give me a letter of recommendation that will amount to anything, as I did not do research with anyone else.
I still want to go to graduate school in mathematics, but I think my chances are even worse now. What are the routes that I can take at this point? If any.