Your observations are so interesting because they form a sort of dance that has been going on since the end of arranged marriages.
I’ll add a couple of steps to your excellent summation of the experience for many men: fear of rejection, a willingness to say or do anything to satiate an all consuming desire, total confusion about mixed signals, followed by frustration, feelings of rejection, and, unfortunately in some cases, angry reactions.
Strong direct communication from you is the only way to avoid causing all this unintentional pain and collateral damage. What would you have said to that first boyfriend to create the healthy boundaries you wanted?