So I have been with my boyfriend now for 5 years. Since our freshman year of high school, we are now freshman in college. Our relationship has always been good until lately I’ve let my insecurity get the best of me and I can’t help it and I don’t know what to do. I have dark brown hair and dark brown eyes. I have a flat chest and am not super skinny. I’ve always known my boyfriends type is blonde hair, green eyes, big boobs, and super skinny. I am the complete opposite of that. He’s never really cheated on me but whenever we do get in arguments because of something stupid he does with a girl while we have been together (danced with a girl, flirting with a girl, hitting a girl up, groping a girl, etc.) it is always with a skinny blonde girl w light eyes. All of the girls he follows on social media that he doesn’t know are the same way and same with the porn he watched. And if just makes me super insecure because I feel like he doesn’t actually like the way I look. Whenever he is talking about stuff he likes about me, he has never listed my eyes, my body, or my hair. Since we did start dating so young I feel as if I was just his only option at the time and so even though I wasn’t his type he still took me and now he’s just kind of stuck. I’ve brought this all up to my boyfriend and he doesn’t understand. I don’t know how else to word it? Can anyone help me express my feelings or am I just over reacting

You are both being insecure, understandable for your age.
I think we all experience this to some degree.
I always thought I was attracted to a certain type, but would fall for men outside of that type over 71 years, and I think some of them had some of the same feelings.
Insecure people dwell on it. Healthy people accept it as normal and don't let it bother them. (I can't claim to be as wise and secure as I sound here! I was plenty insecure too.)

It isn't our job to talk you out of insecurity, because you are the only one who knows the whole story, day in and day out.
If you can't both have a real solid discussion together, you should break up.
But what's this about him 'listing' what he likes about you? OMG, that's needy on your part, if you are asking him to tell you.
Liking, loving, caring, supporting, sharing, compromising, struggling through life together - that's the 'proof' you don't get in a superficial list. Words are not needed. What is needed is a sweet gesture, a touch not related to sex, a smile, and yes, a compliment here and there, support when down.... if you are feeling that you aren't getting them, say so at a time when you are getting along well, and talk about ways to work on more 'expression' of feelings (something typically needed more by women).
Good luck.

I am blonde, round, and flat chested, BTW. The love of my life seemed to find thin, brunette, energetic women appealing. Two of them especially. I asked about them and he looked surprised. Oh no, he said, not for me. I have a feeling your bf is equally surprised. EVERYONE deserves a sort of secret fantasy life. It's healthy and helps keep a relationship together. What can be difficult is getting out of hand about daydreaming or spending time online with others or too much porn. There's no set 'rule' about what is healthy. A couple has to keep talking and working on ways to solve problems, almost like you are problem solving at a job.

You still are learning what love really means over the years.

Good luck sorting it out.

Just based on what you wrote I think you are over reacting, or are afraid to dump this guy who flirts with other girls and gropes them in front of you. Such bad behavior would certainly make you insecure if their was no resolution to this problem. Was it addressed to your satisfaction, or does it continue?

If you think he stays with you because he is just stuck, that is a huge red flag to your dissatisfaction and maybe YOU are the one who feels STUCK. Something to consider since most high school romances never last far beyond graduation. Maybe and it's highly likely BOTH of you are too dependent on this relationship to be healthy, and are not happy being stuck with each other.

Not good when adults are still in a high school relationship and it hasn't grown beyond it. Bet you both still live at home and are you both in college AND working?

There may be a whole lot of other things besides the relationship going on with you two, there usually is.