So, I've actually been feeling pretty ok, but I feel like I'm struggling with the sadness/shame that comes from the numbness that addiction to porn, technology, and masturbation has caused me to feel. There are parts of me that I absolutely hate. I'm trying not to feel them, most of them are probably from the yetzer hara, that voice that tells me how horrible I am, how not good enough I am, how I'll never amount to anything, how I'm not deserving of any of the blessings that I have. I don't want to feel this way, especially since I know that it's those very same feelings that cause me to want to act out. Would love some advise or words of chizuk from anyone who has said enough is enough and pushed the yetzer hara and his advances away!

I can relate to this and I think many many of the chevra here could as well  
Like you said its basically a viscous cycle the y'h gets us in - the most difficult time I have staying clean is when I'm not feeling good about myself which is usually not even called for - it's just my Lust Damaged self esteem
getting to me.
For me it takes a lot of focus on being happy with myself as well as tefillah and taking long walks with some Dmc with Hashem AND with myself (put away your phone for this one..)
These things help me although its still a work in progress .
I'm sure others will have plenty of other ideas its worthwhile to try to be in contact with some people it helps to figure things out .
at the very least click on Hashemhelpme and read through his posts it's full of ppositive chizuk and suggestions regarding these challenges 
Hatzlachah!

As a response to what you are feeling, which by the way I would assume everyone here felt too - I definitely did and suffered immensely from it - here is a vort which puts things in perspective ;

The Tiferes Uziel explains that the letters Bais Gimmel Daled which we recognize as beged - clothing, also form the word begidah which is another word for aveira. "Vatispeseihu b'vigdo laymor shichva eemee" The yetzer hora (symbolized by Potifar's wife) grabs onto an aveira we have done and says "Stay with me. You are a loser anyway! You just did this horrible sin so just give up and keep on sinning because there is no hope" What do we respond? "Va'yaazov bigdo b'yada va'yanas ha'chutza" We say to the yetzer hora "You can keep my aveira, but i am out of here. I will not stay with you. I will get better b'ezras Hashem" Chaver, this vort was written long ago but definitely had you and me in mind!

Wow, what great responses! I have a whole dvar torah on the shalsheles above "vayimaein" when Yosef adamantly refuses eishes potifar's advances- the idea of the shalsheles symbolized by a written and musical ladder, the idea that the only other places that this rare trope happen are in places where people are either stuck onto gashmiyus or crying out to Hashem, it's definitely very powerful and I thought a lot about Yosef's struggle this past Shabbos, it was a big chizuk for me that even a huge tzadik like Yosef needed to get shaken up by the image of his father and rebbe, Yaakov Avinu. I think there was a recent GYE boost where Rabbi Y.Y. Jacobson was talking about how by Yaakov refusing to give up on Yosef, it helped Yosef refuse eishes potifar. Chevra, we CANNOT give up on each other! I find that all of these divrei chizuk are such powerful tools to help me when I'm feeling lust hungry and vulnerable to the y"h's old tricks. Yasher koach! chazak chazak v'nischazek!