I'm going to ditch my best friend for my girlfriend
What is your reason for choosing to ditch your best friend?
I feel like my best friend is not a good person for me to be hanging around. My girlfriend and I have much in common as well.
Wanting to spend more time with your girlfriend is normal but it is not good to ditch your friends to do it. If your relationship ends then you will be alone.
My girlfriend and I are going to date forever and she's going to support me with my future.
Well that sounds terrific that you found a partner that is willing to do this. However, just because you have a girlfriend does not mean that you should leave and forget your best friend.