A bit of help needed. Thank you all so much. <3

I have been having problems with my SO for about a month. It has reached a climax in the last few days. 
I am 23, and they are 26, we have been dating for about 3 years. We have been much in love since the first day we've met, about 5 years ago.

This is what's been up.

I will call this person Sam from here.

I've been having problems contacting them for about a month. I will call Sam at night, and they will either not answer or will answer and quickly say they will call me back (but never will). During this month, I also was working and going to school, both full-time. But I would still call, just to talk.

Sam works a lot, and they have sleep problems. So whenever they said they were busy with work clients, or fell asleep before I called them, I thought it was okay... but I would get kinda bummed when they would not call me back at all.

So. In the past week, the no-answers and no-call-backs were really beginning to fire me up. Sam called me on Sunday, at about noon,  filling me in on their life up to now and what problems they have been facing and what they have been enjoying. I listened and conversed. But when Sam was done talking, they wanted to cease the conversation to carry on with their day. I took issue with this. Wait a minute, I wanna talk about what's been going on with our communication. What the hell is up? Also, I have a few things I wanna talk about.

Sam said, "I don't have time for this right now. Wait until Monday. Then you can chew me up all you want."
"Are you even going to pick up your phone on Monday?"

So then, Sam kept wanting to hang up, and told me I always have this problem. I got very frustrated... they began dismissing me and patronizingly agreeing to everything I said to get me to shut up. I got really pissed, and blurted, "Do you love me?!"

Sam said they were insulted, told me to cheer the fuck up, and promptly hung up in my face. No contact after that all Sunday.

On Monday, Sam texted me. They said I really hurt their feelings and ruined their day by what I had said. How dare I question if they love me or not. They told me I have some serious depression issues I have to deal with, that they are not avoiding me and will talk to me when they are of sound and calm mind, and that they will no longer communicate with me at all on the weekends...

I left my phone at home before I noticed the text and attended class. I finally got the text at 8 pm, and I texted a response. At first, i texted Sam about how I was upset with my issues constantly being dismissed. But I sent a second apologizing, telling them I had no intention whatsoever to hurt their feelings at all, and I never would purposely hurt the, No response.

I would never hurt Sam purposely. Ever. And I do know that my questioning their love was uncalled for... I said it out of frustration, but I still have no right.

I will say, yes, I have depression. My luck has taken a giant dump on me... but I find it unfair for Sam to lump up my issues with them with what I have been dealing with... But that is their opinion, and maybe they view things in that way. I want to try to clear up that I am not lashing my problems out on them.

It hurts giving them respectful space to talk to me when they are ready... especially after all of this time of limited communication.

I just feel as if Sam has not been involved in my life. I am involved with theirs to the utmost I can and what Sam will allow me to be. But Sam didn't even know WHERE I was working until I was there for a whole month, even after I told them repeatedly. This just made me feel as if they are disinterested with my actual life...  
Sam always said that they would be in my corner for everything in my life. But I can't even reach them to talk.

As far as shitty luck here is the whiny list of things:
I lost my job this week.
I have no money because the job didn't have the funds in the check they issued me, so I can not buy basic needs items until the pay posts in my account.
I have no real food in my home, and I struggle to eat regularly, and cannot get food aide due to me being a student in my state.
Due to joblessness, I spend more time at home, which is depressing because I NEED to be busy.
And being at home means I must face my emotionally abusive mother. 
I have anxiety and Seasonal Affective Disorder.

That list is not for pity. But just a background, providing a feel of what I have been going through and the emotions that follows.

I guess I'm just looking for general advice... any advice at all.

Also, do you think Sam is being manipulative by using lack of communication with me? How long should I wait to call Sam if they do not call me?

Thank you for letting me post... and for reading. 
It has helped just to write it. <3 xoxo