Unsure if I need venlafaxine

I’m a 21-year-old guy and for about 3 years I’ve been dealing with a very low mood. Before this, I had never taken psychiatric medication or done therapy. I’ve lost pleasure in things I used to enjoy, like playing video games. I go to work without problems because it really stimulates me and involves things I’m passionate about, but once I get home I can’t manage to do anything. I also experience a kind of constant derealization — it feels like I’m seeing the world through a camera. When I got a tattoo about 2 years ago, I felt grounded in reality for a few days and actually felt alive and present again. I felt the same thing a few weeks ago when I got a piercing (probably similar to the sensation that leads some people to self-harm, even though I experienced it indirectly). I have a strong fear of abandonment with new people I meet, especially those I get along with and want to keep in my life. I start thinking they want to distance themselves because I might seem sad or not fun enough, so I do exaggerated things to prevent them from leaving. This usually has the opposite effect: they notice my behavior and actually pull away. At first I didn’t realize I was the problem and thought they were, but months later I understood after asking two people why they distanced themselves — they both gave the same reason. This month I contacted a mental health center in my area. I was told that before starting therapy I needed a psychiatric evaluation (I only wanted psychotherapy, but apparently this is standard). The appointment lasted less than 40 minutes. We talked generally about my mood, daily life, difficulty doing things, and fear of abandonment, but we didn’t go into much detail — for example, I didn’t mention derealization. I was then prescribed 75 mg of venlafaxine without much explanation of side effects. I started reading experiences on Reddit and found many negative ones, especially about stopping the medication. While people are on it, experiences seem mostly positive. I wasn’t convinced about taking it because it felt prescribed too lightly and because I never intended to take medication — I only wanted therapy. To be safe, I went to a psychologist for a second opinion, and according to him, the psychiatrist did enough assessments and made reasonable choices. This morning I took my first pill of venlafaxine. So far it’s fine, but I am COMPLETELY terrified of dependency symptoms and even more terrified of stopping it, since I know it can be very hard to discontinue. I’ve also heard about brain zaps, which I absolutely do not want to experience. Even being physiologically dependent on a substance scares me. From what I know, it seems possible I have something like borderline personality traits. I see many similarities that could potentially be improved with DBT therapy alone, just like depression. My life is moving forward, even with difficulty, so I wonder: do I really need this medication? I feel like I could improve without it. What has your experience been? Do you think the choices made were reasonable? Thanks, and sorry for the long post.