I've been going through a lot of troubles in my first relationship that I'd like to find some help with. 
Little background, I've known about my BPD for only about a year now, I also struggle with social anxiety, Bipolar, and general anxiety disorder (Deadly mix). 
I'm currently on Effexor, which helps with the anxiety to an extent, but doesn't help BPD at all (Not sure if BPD can be treated with medicine, I'm still ignorant about my own diagnosis, lol).

I've always been a loner and the 'weird' kid, never had good relationships with anybody really. I just recently started making real friends and I'm about to graduate highschool, so yeah, kind of a social outcast.
My self esteem goes up and down, also I don't currently battle depression or anything too serious like that, no suicidal thoughts.

Anyway- I've been dating this guy for about 5 months now, completely fell for him immedietly and those feelings didn't change, even after the honeymoon phase.
Right now it's a long distance relationship, but we make plans to see each other when time allows.
So our main way of "hanging out" is over the phone just sitting in a call doing our own thing or sometimes playing a game or watching something together.
We both enjoy each other's sense of humor and company (I enjoy his at least, not certain how he feels). 
He's a very sweet, loving, dorky guy and I adore everything about him, wouldn't change a thing.
The real issues come and go, I'll have a good few days with him, morning and night texts, some calls in between, and everything's good.
Other days, more problems add to the list, I know damn well this is all in my head but my head makes it seem more real.
I want to not worry and be comfortable with him but goddamn it's hard.

-I get easily unsettled when he doesn't send a good morning text back or respond all day (he's not great at messaging).

-He compliments me and is always there for me, so I feel like it's too good to be true and I don't deserve anything.

-I constantly feel like a moron and *never* feel like I'm being myself around him (like I'm putting on a mask).

-We don't have much we talk about outside of how our days went or just small talk, sometimes it's just me being too insecure to try and start a real conversation.

-I need constant reassurance that this is real and I hold my feelings in as not to bother him until I break down and tell him everything.

In reality, there may be nothing wrong with our relationship, bonds and connections take time. But I'm always worried he'll find another person and go be happy with them  (I love him so as long as he's happy I'm okay) But I don't want to live a lie. 
I've had enough lies my whole life. I want nothing more than to be rid of these dumb mental health issues and to feel something real.
I'm afraid nothing I feel is ever real, and I would rather die than live this way forever.

Thank you for reading- Any advice helps.