I think what is really important is that you don't put the feelings behind those thoughts. It is easier said than done, but if your goal is to manifest your ideal relationship with your guy then there is no reason that you need to be thinking these thoughts. Instead, especially because you are moving towards thinking "there is something wrong with me" shift your perception to you. Focus on you for the time being and go general with your thoughts about him and your easy, amazing and love relationship.I think when we have insecurities it means that it is something that we need to confront in ourselves so make sure you are really listening to what your body is saying. If its positive then yes keep going, if it's negative stop, shift your thoughts and continue from that good feeling place.
Visualize yourself with him on Christmas, be positive about it. Just because your reality doesn't have him in it, there is some universe that you guys are already together so act that way and it will flow in the best and fastest way possible into your life. Let go of those negative and destructive thoughts. 

You are so welcome Meg!  Believe in yourself there is so much power within you.