I treat her like a princess and i feel as if tho she wants 2 get away from me when i see her. wat should i do?

hi there, my birthday was on wednsday and i met my gf for it. i wanted to spend the day with her, and i told her my mum wanted to spend the day with me but i chose to spend it with her. I went there for a couple of hours and we made love for the first time on my bday and then she just had a shower and said to me she is going to go see her mate and i said but i wanted to spend time with you. she replied saying i should be with my family even tho i wanted to spend time with her. each time i see her and i want to spend time with her she stays with me for a 2 to 4 hours and then says she wants to go see her mate or cousins so on. i feel as if tho she gets bored with me and she does this all time trying to get away from me after a while. i only see her once or twice a week and want to see her more. i asked her why she behaves this way she said " i dnt want 2 talk about this now, maybe i want 2 much cos on my days off i wants to 2 spend tym wiv u n my friends" what should i do ? help