I want to spend time with my girlfriend
Aside from the obvious reasons, why do you want to spend more time with her?
I want to be more intimate with her so as to express my love freely
Wanting to be closer to your partner is completely understandable and I think you should go ahead and do it. Just make sure not to be too overbearing or intrusive on their life and everything should wrok out great.
No way!  I want my woman all to myself and I want to exclude other people from her time and attention.
The way you describe the situation sounds like you are far too controlling and dominant over your girlfriend.  If she feels that you do not trust her, and will not allow her to live her life, then she will not want to be with you.  Make time alone for intimacy, but allow her to have her own friends and hobbies.