DEAR ABBY: My mom divorced my dad two years ago because he’s an alcoholic. Dad’s a good guy, but when he’s drunk he gets mean and hateful – and sometimes violent.

Mom has benefited from the divorce and is much happier. About a year ago, she met a wonderful guy I’ll call Dan. I like him a lot and he makes Mom happy.

My dad, on the other hand, hasn’t done so well. He blames Mom for everything that’s gone wrong with him and even accused her of divorcing him because she was having an affair (which is absolutely not true).

I will be graduating from high school next month. I can’t NOT invite either parent, because I know they’d be hurt. I also can’t NOT invite Dan because he’s like a second father to me. What should I do, Abby? My fear is that my father will arrive drunk at my graduation, cause a scene or start a fight with Dan. Any advice would be appreciated. – GIRL ABOUT TO GRADUATE

DEAR ABOUT TO GRADUATE: Talk to your father about your concerns. If he cannot promise faithfully that he will behave like a gentleman, do not invite him. Tell him that this is your day – not his, not your mother’s and not Dan’s – and you need to be assured it won’t be spoiled.

DEAR ABBY: Whenever I read in one of your columns a reminder about sending messages of encouragement to personnel in the military, I become frustrated. I would like to send a message, but I’m not sure where to send it.

I want to send encouragement, love and heartfelt thanks to all the gay men and women who serve our country whenever and wherever they are needed. In an already stressful situation, they have the added stress of staying in the closet. They not only have to fear the enemies of our country, but also that a homophobic colleague will betray them.

As it was in the Gulf War, their sexual orientation will be ignored because they are needed, but as soon as the action and/or threat is over, they will be tossed aside as many before them have been.

Please, Abby, let them know that we admire, care and think about them and the sacrifices they are making. – MARTIN IN FORT LAUDERDALE, FLA.

DEAR MARTIN: Thank you for pointing out the unfairness of “situational discrimination.” A person’s sexual orientation has nothing to do with his or her degree of patriotism or ability to successfully defend our country.

DEAR ABBY: My son is a junior in high school and dating “Lynn,” who’s a senior. They’ve been going together for nearly nine months.

Lynn asked my son to go with her to the senior prom. I am unsure about the proper etiquette regarding money. How much of the cost should my son be responsible for?

Keep in mind that it is HER prom. She invited him to be her date. Is it OK for them to split the expenses? My son seems to think he should pay for everything, but I disagree. Please give us some advice, Abby. He’s nervous enough as it is! – SOUTHERN CALIFORNIA MOM

DEAR MOM: Your son should not pay for everything. Even though he was invited, it would be appropriate for him to offer to pay half the cost. They could do it this way: He buys dinner, her corsage, and provides the transportation. She buys the tickets for the prom, his boutonniere and the photographs.

Dear Abby is written by Abigail Van Buren, also known as Jeanne Phillips, and was founded by her mother, Pauline Phillips. Write Dear Abby at www.DearAbby.com or P.O. Box 69440, Los Angeles, CA 90069.

What teens need to know about sex, drugs, AIDS, and getting along with peers and parents is in “What Every Teen Should Know.” To order, send a business-size, self-addressed envelope, plus check or money order for $5 (U.S. funds only) to: Dear Abby, Teen Booklet, P.O. Box 447, Mount Morris, IL 61054-0447.