I did not want to be in any relationships for a period of 2 years, the last year I dated("freakin' good friends" only) the girl who would become my wife. She grew on me, and I adjusted, albeit very slowly, I did adjust to the idea of being in a relationship. What eventually changed my mind was when she decided she had tried long enough(see below), and gave me the impression she would move on, since we didn't want the same thing anymore. The saying; "You don't know what you have before you lose it", suddenly became really clear to me.
We both started out honest about our intentions, none of us wanted a relationship. Then things changed. At first for her, and then, eventually I realized I wanted change aswell.
Aspies and change don't mix well, but spread over a full year, I adapted.
But! ..don't give ultimatums, don't say; "If you don't want a relationship, then I will leave.", I know that wouldn't have gone well with me. What "worked" was when she ignored me for 3-4 days, while she was away on holiday. If she had given me an ultimatum I am fairly sure that wouldn't have worked. And also, if it had happened 2-3 months before it did, I doubt I would have been ready.
The only advice I can give is; Be patient.
..but also, don't waste your prime youth in waiting, it might never happen. There is no perfect answer, every case would be different.
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AQ: 42/50 || SQ: 32/80 || IQ(RPM): 138 || IRI-empathytest(PT/EC/FS/PD): 10(-7)/16(-3)/19(+3)/19(+10) || Alexithymia: 148/185 || Aspie-quiz: AS 133/200, NT 56/200