Suspecting you have a gay boyfriend is something difficult for any women to face, but is an increasingly common situation for people to have to come to terms with. Because in some places being openly gay still isn't acceptable, even if people think they are, they are often under pressure to pretend that they aren't. Because of this many gay people then enter into heterosexual relationships and even sometimes get married and have children, despite knowing that they aren't being true to themselves.
One of the most apparent ways to tell if your boyfriend is gay or not is that they are often inexplicably absent at odd hours of the day or night. For example you might wake up and not find them where they should be, or might be unavailable late at night. Particularly when despite the fact that they would usually always be at home. Many outwardly heterosexual men lead a secret double life of going out to meet other men in the night.
Another good way to tell if your boyfriend might be gay is if he has a lot of friends that you have never met, and that he doesn't want you to. Obviously people who are gay, even secretly usually know other people who are gay. And as such these people are usually kept hidden from the rest of their lives. The reason being of course that they don't want one part of their life mixing with the other part.
Similarly to having lots of mysterious friends you haven't met, strange text messages and even pictures can be a good indicator that someone is secretly gay. If you were to find odd language, or phrases from his male friends that don't quite sound right, then there might be reason for suspicion. If your boyfriend does seem to have a lot of friends that he doesn't want you to meet, it might be worth checking with his friends that you do know as to who they are.
Messages that your boyfriend gets overly defensive over that shouldn't be anything particularly suspicious are cause for concern often as well. For example if there is a message from one of his male friends arranging a meeting that he doesn't tell you about. Or if in fact you ask him about said message and he suddenly becomes defensive and fabricates an over elaborate story, despite you not really pushing for one.
Many men who are gay and yet carry on with the facade of a heterosexual relationship are noticeable in that they aren't very interested in being intimate with the opposite sex. So if your boyfriend is gay then they wont be overly bothered when you are too tired, or if there is some other reason that you cant be intimate with them. In fact in some situations, repressed and latent homosexuals will in fact try to look for excuses themselves.
In years past many people might try to judge as to whether someone is gay through their personal hygiene habits. For example if your boyfriend takes longer getting ready than you do, or if they use a lot of products in their daily routine. However in this day and age a lot of men are more in touch with their feminine sides, and a lot more men are taking better care of how they look. So in short whatever care your boyfriend applies to his appearance isn't usually a good sign one way or the other as to whether he might be gay or not.
Men who are militantly anti-gay are often overly trying to compensate for their true feelings, and are in fact gay. So men who are vehemently hostile when the subject of homosexuality is raised, are often just trying to hide their true opinions. The reason that they are so aggressive about the matter is simply because they often cannot accept who they really are.
Stereotypically people have always tended to look for overtly effeminate gestures and traits to identify whether someone is gay or not. However in the case of someone who does not admit it perhaps even to themselves, this is rarely a useful way to tell. After all people who don't want others to know that they are gay will probably tend to be very good at hiding the fact, rather than being what most people would think of as how a gay person would act.