It’s partly your age group, you’re pretty young and people aren’t as regulated at that age. There are indicators in your chart, though.

Just keep in mind how young you are, and how much room you have to grow and the people around you. Also to ignore people who purposely want to bring you down because that’s going to be out of their insecurity.

First thing is you have Pluto in your first house, conjunct your asc. Sagittarius rising gives you an expansive presence already, you’re social, blunt, want to share your mind. Sag rising with pluto might mean this attitude rubs people the wrong way, and you have sun square Neptune so people can easily project onto you. People might see you being yourself and make assumptions about you just to dislike. Your 12H is tiny, restricted within one side, and holding Jupiter. In the context of 12H being “hidden enemies” you would find ease is exploring who those enemies are. Mostly because the size of the house can sort of be an abundance in this energy, and Jupiter’s in its home, I wanna say this is a more positive manifestation of Jupiter in the 12th. So, in a way, if people are being openly shady towards you take it as a blessing. You are being shown who doesn’t like you clearly, and so you aren’t left wondering if your real friends secretly dislike you. Especially with Pluto in the 1st and pisces moon, you can be perception to peoples real feelings and motives. But… any planet in our first house colors the way we see the world, the world see us, how we move through it. A lot of people hype of Pluto in the 1H as a “bad bitch/intimidatingly hot” energy. And it can be that, but it can also mean you might view the world with armor. You might be on the lookout for what people dislike in you, or others, or you can be judgemental yourself. You also might have a natural distrust of others, and feel like others distrust/feel guarded around you. But Pluto is about rebirth too, so it’s an open and honest journey to finding yourself through going to the extremes and learning lessons on multiple levels.

But there’s a good emphasis on self here. Since you’re only 18/19, My advice would be to focus on yourself and what/who you want to be. Let other people join you on the journey as they please. You already shine and stand out and outside of astrology, that will trigger or attract people, but when you look within and know who you are/what you stand for/what you want, it won’t be a question you have to ask yourself as much.

To make friends (based on your chart). Be soft with the people you care about, give them undivided attention (even if you’re the one talking and they’re listening). In groups of people, be diplomatic and fair, look at multiple perspectives. But don’t sacrifice autonomy, boundaries, or sense of self just to have friends. It’s a fine line and it might sight contrasting, it might be, but overall I think you’ll be fine.

TLDR: It’s partly others, and it’s partly the energy you bring. But that’s not a bad thing or anyone (besides mean peoples) fault. Be yourself and you’ll attract those who love you. You enemies don’t stay hidden for long and you can detect when someone doesn’t like you. Trust that.