Feeling a little alone in my demisexuality

I apologize in advance for the block of text!

Background info: I've always known something was off with my sexuality but couldn't figure out what. I was with a guy for 4 years (began in high school, continued into university) and felt a need to be sexual with him because I thought I was abnormal to not want sex, and would often force myself thinking eventually it would be better. We went about a year without sex, which was honestly great for me, but led to him cheating on me, etc. We broke up in February 2016, and it was probably the best thing to happen to me. I thought that relationship was great when I was in it, but coming out of that relationship I realized how messed up it was and how little I understood about my own sexuality.

Originally I thought I might be asexual, but last summer I discovered the word "demisexual" and what it meant and knew that's what I am. Everything about my relationship with my ex made perfect sense, and also explained why I never found people sexually attractive in general.

I ended up in a casual relationship last summer to kind of explore the demisexuality and figure it out a bit more, knowing the relationship would go nowhere and end when he moved away at the end of the summer. I'm glad I got to use that time to explore.

In October, 2016 I met the guy who eventually became my current boyfriend. Ironically enough, I found him on Tinder. Again, I was trying to explore my demisexuality and figure out if I could find people attractive/sexually attractive, etc. He was honestly the only guy I found attractive from the photo, we hit it off, and the rest is history I guess.

He's an AMAZING boyfriend. Like more than understanding of everything. He's bisexual, so he understands the erasure problems I often experience, and appreciates that my experience with sex is drastically different than his. He's a sexual person. He has 25 sexual partners from the past couple years (as opposed to my 3, including him). I have absolutely NO problem with this, and he took sex very slowly with me because he knew I needed a bond to form before sex could even be a consideration (I was upfront about the demisexuality).

Anyway, fast forward to the current issue at hand:

The past couple weeks I've felt particularly alone with my demisexuality, despite knowing that I have my boyfriend as a support. He is 100% willing to listen to me, is never judgmental, but I still feel like there's a level of understanding lacking slightly when I talk about my issues.

In particular, I've been feeling alone in the erasure. I've been pretty upfront with everyone (family included) about my demisexuality, and most of my family members are cool with it, might ask a question or two, but move on afterward, but I do get the occasional snide remark insinuating that demisexuality isn't real, and that that's just me having standards. My stepmom tried telling me my demisexuality is just normal behaviour for women, and she "knows" this because she also doesn't like one-night stands (obviously ignoring the rest of what I've told her about my experience). And just this past weekend my best friend told me she had mentioned to her friends (who are gay and bi and in a relationship with one another) that I was demisexual recently (which is cool with me, I don't care about being outed and she knows that), and the response from her gay friend was to say that demisexuality isn't real.

Beyond that, my boyfriend and best friend have both also made remarks that they DEFINITELY didn't realize felt like erasure to me, but did. My boyfriend kind of jokingly said one time that I don't understand what meaningless sex is because I'm "not LGBTQ+ enough." And my friend almost always starts any conversation that involves sex in any way with "you might not understand what I mean because you're demisexual." I KNOW they don't mean anything hurtful by these comments, but it still feels alienating. Like I'm somehow not normal for the way I am.

It took me SO long to find out the demisexuality is a real thing and I'm not just weird, and I'm SO glad I figured that out when I did, but the problems with my demisexuality are starting to shift I guess. What started as thinking I was weird because no one else was like me, has turned into me thinking I'm weird because people around me still don't see it as totally valid.

I don't even know what the purpose of this post is. I'm just feeling alone, and don't really have people to talk about it with. I guess I just wanted to get those feelings out in a place where other people might feel similar.