Hi, I'd say that there's nothing wrong at all with needing "someone" around and wanting the attention of the person/s you're interested in, needing to be "loved".
Most people are going to feel like that to different degrees. As long as you can still feel good about/in yourself, like yourself for who you are without that depending on someone else/anyone else. And of course, that you're still recognizing/respecting/valuing the other persons/people's needs/wishes/individuality in all of that too.
With some things you've said though, maybe just the way I'm reading it but do you think that when you're out of your "comfort zone" e.g. with not with family or close friends you can feel a bit insecure/lack confidence/feel a bit overwhelmed perhaps?? Just a thought......
Anyway, you say you prefer quieter environments like it's a bad thing? Unless that's really impacting on what you want to be doing/how you want to live your life it really doesn't have to be bad. Some people just do prefer quieter environments, everyone's different. Maybe try to find activities/things to do with others in more laid back settings or link in with other people who share the same preferences as well if that's just "part of who you are" assuming you'd still be getting enjoyment/satisfaction in more of those kind of settings and maybe just try the noisier (?) settings occasionally for a change/bit of diversity if you want to/feel like it.
From what you've said it does sound like panic/anxiety attacks you've been having in the more crowded environments though. Still....sometimes can be ways around those, depending on where they're coming from and how bad they are.
Could you keep a bit more "on the outskirts" when in places like that? Focus on certain things/people? Try to pinpoint the signs when you're just starting to get anxious and tell yourself something reassuring....repeat, repeat, repeat if necessary? Try some deep breathing exercises? Focus on when you're going to be out of them if you have to?
But why do they happen- well there can be lots of reasons e.g. negative experiences previously, fear of something happening (even if the chances are so tiny of that something happening), fear of other peoples expectations and living up to them, stress............
But sometimes just the experience of having a panic attack can cause either the chances of having a panic attack, or the amount of panic you're having while you're having one to escalate so much more. There's a really good forum on Anxiety, Panic (and Phobias) on here though, so maybe worth dropping in and taking a look?
And as for the sexuality bit, that's really good that you/others are fine with it. You/they should be!!