Too afraid to ask but do guys assume alternative girls only want casual hookups or are walking red flags?

I feel really awkward asking this but I do not have any guy friends in real life to give me an honest answer. I am an 18 year old girl and I feel like I am sending completely the wrong signals to men.

I dress pretty alternative. I wear a lot of dark makeup black lace and big boots. I also swim a lot so I am in really good shape but I usually hide my body under oversized dark clothes. The problem is guys at my college or at the restaurant where I waitress either avoid me completely or they only try to talk to me for really gross casual hookups.

I was complaining about this to my older ex boyfriend and he told me it was my own fault. He said dressing goth makes me look easy or unstable. He told me no guy is going to want to take me seriously court me or start a family with me someday if I look like an edgy weirdo.

That honestly crushed me because it could not be further from the truth. I am actually super traditional and kind of a boring nerd. I spend my weekends just studying for my architecture classes and playing chess online by myself. I am not into casual hookups at all. My absolute biggest dream is to be a young mom and build a real family with a guy who actually loves me.

So I just want brutal honesty from men. Do you guys automatically see goth girls as just a fetish or a red flag? Do I need to start dressing like a normal vanilla girl if I want a guy to actually take me seriously and want a future with me?