Stop taking things for granted. Just STOP, you've been doing it all your life and it's time to change that habit.
I think you have a problem. You never appreciate what's in front of you, whether it's material things or inter-personal relationships with friends and family, or even life in general. You know this has been a common occurrence for too long, the biggest problem and imo the biggest contributor to your downfall is that you don't know HOW to appreciate, how to even FEEL appreciation. You accept positive occurrences as part of the norm when instead, you should realize how fortunate you are. Wake up and snap out of it, learn to appreciate life and you'll have a better outlook. Stop deceiving yourself when something good happens, it's mostly due to being fortunate, not because you're just that awesome. There are times when you do feel grateful and fortunate and appreciative, but those feelings are fleeting. They're temporary sources of joy that quickly dissolves. You need to hold onto those feelings, and do whatever you can to show it.