I feel for your friend because my mom had acne until (I assume) she hit menopause, and my acne starts back up if I ever take a break from continuous birth control. Doctors are also incredibly dismissive about these things because no one understands female hormones -yay for us!!

I can’t diagnose your friend, but I can point you in some directions to bring up at the doctor:

Starting about 2 years ago her face started getting acne, and any treatments just made it worse. the only thing that helped was antibiotics.

What treatments? (you don’t have to tell me, but have it ready for the doctor) Usually they’ll hand you some benzoyl peroxide and salicylic acid along with the antibiotics as the initial treatment. Maybe tretinoin (retin-A). These are very harsh actives, so they can be very irritating if you use too much or don’t combine them with a skincare routine. They also just don’t work for everyone. She can go back to the dermatologist and try something else.

Some of the spots are very tiny, like pore-sized, and get white heads

This sounds like it could be fungal acne (again not qualified to diagnose, go to a doctor). If it’s itchy and also gets worse with heat/sweat, try some anti-dandruff shampoo with ketoconazole or zinc pyrithione and see if that helps.

Before her period she gets very irritated-hyper, one time she got so pissed off at a pretty mundane thing she threw a mug at the wall.

She should speak to her doctor about PCOS and/or PMDD. They will likely recommend birth control for these conditions if she has them, but that is not the only option if she doesn’t want to go on it.

she says she only looks young because she has big eyes and a small nose

“Looking young,” “big eyes,” and “small nose” could be indicators of various genetic or endocrine conditions, but I wouldn’t bring this up to the doctor since it’s super vague and doesn’t point to anything in particular. She should just stick to symptoms that are bothering her. Presumably the doctor will be able to spot the connection if there is one.

Since 31 is still very young, is this normal for her age?

I don’t think this is a useful question. Acne is a common condition even in adults, but it is still a condition that most people want treated. The point is she wants treatment. If a doctor dismisses her with a “oh it’s normal” or a “it’s just a sign that you have young skin!” (my mom got this line into her 40s…), go to a different doctor.