A certain part of the male population, especially among the frat guys, has a rule saying "Bros before Ho**" . I believe your Boyfriend follows that. Not everyone is like that though. But yeah I agree some are like that.
I have had most my friends for several years. Most girls I date about 6 months to a year. There is no comparison. That is not to say there are not times with he should put you first, but you can't be first all the time.