Why do I feel like I am different than other people?

I want to bring mental illness out of the shadows, and I want to let people out there know that I am not that different than you.   I have hopes and dreams, I have good days and bad days, I often just want to sit on my couch and watch Netflix after a long day of work.  
So, why do I feel like I am different from people who do not have mental illness?
I also have diabetes and thyroid issues, but these illnesses do not make me feel like I am different, like I am walking on a separate path from other people.   I still have to take care of my self with these illnesses, I still have to take medication, and make lifestyle choices that make sense- the same way I do for bipolar.  Yet the word bipolar seems so much more loaded than diabetes or thyroid disease.  So I wonder, do I feel this because I have been labeled as 'having a mental illness?'   And does that label make me feel like people would treat me differently than they really would?   Or does this difference really exist?  Is bipolar really all that different than other medical illnesses?
Both thyroid issues and diabetes can affect a person's mood, yet they seem so harmless and innocent compared to 'the big bipolar'.  
I have also heard terms like "THE MENTALLY ILL"  used in ways like:  Keep guns out of the hands of 'the mentally ill'.   No one is saying keep candy bars out of the hands of "THE DIABETICS"   or watch out for "THE THYROID PEOPLE" because they will get you if their medicine is off.
Why is that?
I had a casual acquaintance say something very offensive to me one day about my bipolar illness.   I had talked to her a little at my past job because she was new to my area and had some questions about childcare in our town.    I left that job shortly after she started to take my new job as a peer support specialist.    I saw her in one of our public pools shortly after that, and she was asking me about my new job.   She asked me "so what is a peer support specialist, and who are you a 'peer' to?
So, I took a deep breath, and I told her.   She immediately responded with 'oh, I know all about PEOPLE LIKE YOU, I went to art school and art school is full of manic depressives.
Keep in mind that this was like the first two weeks of my new job, and I was just getting used to telling people about the big bipolar, just sort of getting used to tasting those words in my mouth, and this lady is telling me " oh I know all about you"    just like I am some equation of bipolar + crazy = bullshit.
So if I was a peer to diabetes or thyroid disease would she have told me that she knows all about me?
Oh, I know all about you diabetics and how you roll, or I know all about you thyroid diseasers, and just exactly how you are every minute of the day.
Maybe this is why I feel like I am separate from other people.   Why I still hesitate with those words, those words that seem to define me to some people.
I am not defined by sinus infections, or asthma or diabetes or thyroid issues, so why am I defined by bipolar?    I after all, am a person.
If I have a head cold, I am not 'the head cold'.  I am simply just a person who has a head cold, or a person who is suffering from a cold.
Why can't I be a person who is suffering from a mental illness?    Or a person who deals with bipolar?
At the end of the day, I am still me.   I still want to sit on the couch in my fat pants after a long day.  I still don't like going to bed with dirty dishes in the sink.  I still love my cat, love my daughter and love my family.   I shop at the grocery store.  I go to thrift stores.   I love flea markets.   I make tutus for my daughter.  I water the yard and plant a garden.   I go camping and hiking in the mountains.  The only difference is that my highs are a little higher and my lows are a little lower.
I may wake up with my mind going really fast.  I may have many ideas.   I may want to reorganize my whole house at 2 am.   Or I may wake up feeling numb and heavy.   My body and soul feeling weighted down with misery, like I have lived a thousand long hard years.  I sometimes struggle with getting out of bed, or with liking myself and my life.  But I take my medication, I put one foot in front of the other, every single day.   I use wellness tools like DBT and WRAP to get myself up and out into life.  
Just like any other person does with any other illness.
So why do I feel so different?
Here is a video by Kelly Clarkson called 'People like us'.     I heard it in the car the other day and I felt that it was very empowering.  It celebrates the differences in all of us, and how the world is beautiful because of differences.   I hope you like it!
Kelly Clarkson Video on You Tube