Oh god, this is heartbreaking.
OP, stop "hoping he'll change and show you more commitment". He isn't that into you - and you seem happy to accept the crumbs and "go along with what he wants".
Part of the reason you feel so needy and insecure is because HE makes you feel that way - forcing you to push/beg for markers of commitment (like figuring in his plans, feeling able to ask to see him over Christmas, wanting him to make the effort to split the travelling, etc) rather than giving them to you freely.
I know you aren't going to dump this guy (although you should, he'll grind you down and waste your time) so rather than pushing him to like you more, would you consider trying to improve other areas of your life and raise your self esteem?
Do activities that make you feel good - that might be hobbies, sports, seeing friends, volunteering, education - something to give you a bit of pride in yourself. Read books about things that you enjoy, find a passion for something, do something that makes you feel good.
Stop trailing around after this guy like a puppy - be a bit busy yourself at the weekend. If you don't think he'll bother with you if he has to do a bit of work to see you, then better you find that out now, surely?