Peter is still interested in women, as he's married to Lois, has had several relationships with other women before her and continues to cheat on Lois with other girls in the show but there's no denying that Peter is also very attracted to men, making him a mostly-hetero swinging bisexual man. Sadly, Lois dumping him would not be a poor decision, as Peter has been shown many times to continue having relations with other men, despite being married to Lois, making him an adulterer. Over the years, Peter has had several romantic and sexual relationships with other men although he doesn't like to admit it, due to either the fear of being teased by his friends for his sexuality or possibly out of fear of his wife seeing him as 'unfaithful' and dumping him. However, as the series went on, the jokes became more prominent and harder to ignore to the point where it hinted that this might be an actual part of his character and that Peter could be bisexual. At the start of the series, these jokes were few and far between and could easily be brushed off as one-off gags.
Peter's Bisexuality is a recurring theme in Family Guy involving jokes about Peter Griffin being bisexual.
