As a hobbyist, I'm 4.5yo. But since last Oct, YMMV seems to be just for me.
Is this some kinda one of hobby phases like some fluctuation? I don't even know whether hobby phases exist. Or simply just my luck for 4 months. what the heck...

Not sure do you feel like your in a rut?  Maybe you need to change your search parameters.  You could be evolving.  I find that what is going on in her head changes everything.  If I get a mind connection then every thing else falls into place.  Just my thoughts

If this has occured numerous times over a five month period, something is up.

It could be your hygiene, mannors, topics you may bring up, etc.....something is going on where the girl is not comfortable with you.

The more comfortable I am with someone, the more open I get.

What are you doing differently than you did for the first 4 years?

something changed it would seem.  Try something new and look to tried and true providers as well.