the same situation is happening with me and my bf, only it's the other way around...so from the perspective of the other person, as i'm sure you know, the way you feel and the inevitable way you come off to him as you're so afraid to lose him, will only push him away. it's a form of insecurity. i'd say what's causing your SO to act a bit more settled is that he's just more comfortable in the relationship, and doesn't feel like he has to do something (i.e. be super attentive) to impress you to stay in the relationship. it's a higher level of comfort that comes as the relationship goes on. for example, in my relationship, i'm secure in how i feel towards my SO and the relationship, so when i keep getting signals and messages that he's insecure about it, i'm really baffled, and the insecurity always mushrooms into something that negatively affects the relationship. if i don't really think about it, i wouldn't be aware of the fact that all the signals i was sending in terms of how comfortable and settled i was (which is a positive sign of the relationship to ME) was actually sending him signals that the relationship could be going awry, causing him to fear losing me. so i think just to understand what he may be thinking is helpful, and you have to relax a bit, because it definitely isn't HELPING your relationship........what i do whenever i feel insecure is to repeatedly tell myself, whatever happens happens, and if it's not meant to be, then it's not, and something else is meant for me. similarly here, trust in your relationship and your feelings towards him, and that he reciprocates these feelings. if he doesn't, then it wasn't meant to be and there's something else out there for you. hope that helped!