My jealousy and insecurites are killing me...

and making me constantly depressed in this relationship.
I have been diagnosed as having mild depression and anxiety, and I'm supposed to take medication for it, but within the past few months I haven't been taking it because it just seems to not do anything for me at all.
I'm such an insecure and anxious person. I trust and love my boyfriend very much, but I always get SO extremely upset even when I see him talking to another female. I feel awful for acting the way I do, but even as hard as I try, I just cannot do anything about it.
He isn't really the problem here, it's me. I'm the person who starts the arguments (from my other post, you'll know about his female friend, which is mostly what we argue about), and gets so jealous and upset. It feels like to me that he really enjoys being around her, and I'm so boring. I'm CONSTANTLY worried. I stay up late at night crying and being so anxious because I feel so upset, about what? It's so stupid of me. But I can't help it.
A big reason why I become insecure about this relationship is actually a really ridiculous reason. He follows many girls on twitter that I don't know, and talks to a few of them often. Also once, he basically declared that he'd absolutely love to see Taylor Swift naked. He even follows her too. And I know it isn't because he likes her music (he only likes metal). That bothers me.. SO much. I can't stand it.
I'm so tired of feeling this way.

You should focus on your depression and anxiety issues. Does will make anything seem unbearable.
Check my sig for tips that might help you in the long run.

I think the main reason for him to see other girl is your depression and anxiety issues.Because a boy don't like a girl who is depressed and cry on small issues.So i think you should change yourself than you can change him.

I understand feeling like that so well. I'm BPD, so mine stems from that, but in the end it's still the same. Have you guys really talked about this? Maybe try and compromise on what is acceptable, and if you guys can come to mutual terms then you can focus on accepting them. That's what worked for me (not saying I'm healed, very far from it) but I'm improving. And also, as difficult as it is, remember that he is with you for a reason.
Now something I struggle with as well is my bf being around other girls (guys trigger it too, but girls especially). If it bothers you, perhaps ask him if he can stop talking to her. Maybe it seems low to some people, but it doesn't hurt to ask. You can trust him completely, as I'm sure you do, but still be insecure and scared. I really don't know what else to advise here, I'm still looking for the answer myself.
Don't be afraid to bring it up. Communication is key in recovering from this problem. And if he is talking to another girl because you have depression and anxiety problems then he really isn't even worth it.
If you need anything, feel free to PM me. I know how difficult this really is.

I think the main reason was lack of confidence.You don't try to face the problems and you get more depressed.Which also increase the prob;em and you also make more mistakes.So you must be confident and try to face all the problem that happens in your life.

I read a number of your other posts, I can't comment on your boyfriend and his interactions with his female friend but from this post you have here, you do sound a bit like my ex. My ex is like you, perhaps not exactly but more or less quite insecure and can get very jealous. I'm gonna give you a perspective from my end as a boyfriend.

There are at least two occasions that I know of that my ex went into my phone and check if I was receiving texts from other girls. There's times when I'm checking my email and she snoops from behind and nonchalantly asks me what that email is (expecting me to open it for her). She scrutinizes every single female friend I ever have, even on facebook. One time during lunch break we was walking and I saw my friend and I tried to say hi to her, she just flipped out and walked off away from me. Then she spent the next hour calling me up repeatedly at work but having little to say but did it just to annoy and vent her anger at me. (I've really hated her for that) If there is an attractive girl walking by, and I'm caught looking then I'm gonna get hell for it. If I'm watching something on the tv or PC that happens to have a cute girl in it, she calls me out on it. It's so bad it gotten to a point where I just have to take out all my female phone contacts off my phone and for the longest time I even avoided FB. For those two and half years I was with my ex, I hardly dare to hang out or reach out to my female friends. It was that bad.

The sad part is that I never once cheated. I'm not even a flirty person. Everyone who knows me will tell you that I'm very shy and quiet. But thanks to her past history in which her ex supposedly 'cheated' on her, I'm liable to suffer because of her past experience. I was living a life of a condemned man. People that I know, friendships that I valued who just so happens to be female that she finds threatening, I felt pressured to cut off or limit at best. And like a weak-willed fool that I am, I more or less caved simply because I was so very afraid of drama coming from her. She just has her own unique way of bombarding you and making your life hell with her being emotional and irrational.

The point is, all the nagging, all the drama, all that calling out, it all adds up to resentment. No one wants to live their lives repressed and controlled. All that effort and things she did to "steer" me away from cheating gotten bad enough that I had thoughts of fantasizing of wanting to cheat simply to spite her and simply because I was so repressed. I just want to get away and be with a different person, that was my fantasy. She tries so hard to make my life revolve and focus on her that I feel myself drifting farther and farther away from her (even loathing her for it). I guess you can call it a pull and push effect, the more you try to pull someone the more he'll try to push away. But that's just my ex. Perhaps you're not that bad and I'm not sure if that's exactly the reason why your boyfriend would rather include his female friend in his activities over you. One thing I do recommend though is to talk to him honestly of how you feel (if you haven't already) and especially acknowledging the same thing you did here that alot of it is irrational and that you're aware of what you want to work on. And everytime you feel upset, just try to calm down and ask yourself "ok am I over-reacting?", "is this something that is serious and worth bringing up?", "how is he going to feel and how am I going to feel in the long-term?". I think alot of irrational thinking is due to our need to satisfy our short-term wants and spur of the moment emotions, but we're not thinking of the long-term. It's not something that can be fixed quickly but best of luck.