Ah, many memories arrive to my mind. Bad advice and 'wrong' decisions too. And many learnings. How to be rejected, how to be accepted by yourself and by someone else. Nice memories at the end.
I could assume many things from your text, and I think you want to read other people experiences, so I leave my random thoughts here.
What worked for me (guy in his 20s w/o real life experience looking for girls) was doing the opposite. Instead of asking 'Do you want to have a strong long term relationship with me?' to a girl I've never talked before it was more like, 'Let's be friends', so I friend-zoned first, and a few months later the door was opened to something more. Slow and painful, but this week wife and I are celebrating 9 years of relationship, so... It depends on what you are looking for and what they/he/she are interested in.
Lastly, any advice is useless, every relationship is different. So follow your instincts and recalculate with each try.