<human>: Can you summarize the given text in a few sentences?

I have been with my girlfriend for 3 and a half years and this problem has been haunting our relationship ever since we moved in together. She loves to cuddle and I don't mind it every so often but not every night. 

It starts because she likes to go to bed around 11 or 11:30 and I like to stay up until around 3. She asks me to cuddle with her for 10 minutes or so every night. I would say 3 or 4 nights a week I will do it. Some nights I will even go to bed with her. There are just some nights that I don't want to do it. Those nights she then begs me to go, and I will normally still say no. Then she starts getting angry and calling me selfish. Some times these arguments will last for 20 minutes with her refusing to go to bed. I feel that I should cuddle when I want to, not because I am obligated to do it. 

She says she just wants to spend time with me but an example would be last night I went to bed with her and stayed the whole night. Then tonight she had to work but when she got home I got dinner and we played monopoly after which she wanted to go to bed and I said I wanted to stay up. She said I can go cuddle with her and I declined. Then she blew up and called me selfish for not wanting to spend time with her.

This seems like a small problem but when you are dealing with someone yelling at you for not wanting to cuddle it gets a little bigger.
<bot>: My girlfriend wants me to cuddle every night and I sometimes don't want to. Does that make me a bad boyfriend?