It sounds like the other relationships or at least that one ended with you being dumped was a more familiar role for you. I am wondering if what you might miss is the uncertainty or playing the role of codependent in some way. It would be helpful to take some time and really think about the role you actually played in past relationships that actually may not have been "healthy" for you, but felt right simply because you played a role you were used to playing. Perhaps this guy who is so reliable and thoughtful is a healthy that is good for you, but just makes you uncomfortable because it's different than what you are used to having.

Yeah, but these relationships did not last for you either, did not have what it takes to stand the test of time which is what a relationship needs to continue to thrive. Could it be this seems too "easy" for you? That you feel you need to work harder at the relationship and be the giver? This is important for you to know as you could end up being alone or experiencing relationships that leave you feeling hurt or used because you feel more comfortable in unhealthy relationships, not actually realizing that's the real problem in this picture.