Anxious attachment in adult life - how to overcome this?

Hello. Another guy, another story
If i may, i'd like to go with the facts and refrain from misleading subjectivity (whenever possible!)

Here is my anamnesis: a shell of man in his late twenties, never kissed a woman, never had a meaningful romantic relationship, very few sporadic friendships. Anxious attachment, low self-worth, not very emotionally stable.
The anamnesis is ugly, but it lies in the past; changing the future (the prognosis) is the next best thing. The question is: how to actually get better?

The story so far

Now, let's take the chronological route, starting with this man's early childhood ...
An anxious, sometimes absent mother and a despotic, oftentimes absent father - these were the people who formed my sense of self; they showed me, in their own flawed subjectivity, what the world around us is supposed to be like ... and i uncritically accepted my parents' worldview, as all children do.

The worldview i absorbed had many flaws. I was taught the "lessons of life" - about blindly obeying, not "bothering" others and not annoying them about getting my own needs fulfilled. Moreover, I was taught very little in the ways of emotional expression, empathy and social skills. There were no open communication channels in the family; all they did was pretending that everything was OK. The "perfect little family". Right.
They also criticized - there was no praise for a job well done (only snide remarks about how i could have done this and that better/faster/neater/smarter/etc.)
Being over-criticized in most of the chores and duties led me to developing a protective shell - seemingly uninvolved on the outside, avoiding hurt on the inside. Later in life, i also embraced a nihilist as a part of myself - the motto was "if you can't do it right, why bother".

It is generally known that an opposite sex parent influences their child's future romantic endeavors. The parent serves as a prime reference of what the opposite sex is supposed to be like. For example, a nurturing, communicative mother that raises her son well may be looking forward to seeing her son marrying a quality woman one day ... a woman with a personality similar to the mother's.
In my case, trying to chase girls based on the reference of my own mother (the unspoken message stated that "women are some fragile, extraterrestrial, extra-moody beings who are always the victims of circumstances") led me to failing miserably with the ladies, over and over again. These were my romantically tragic late teens; with some mutations, these fails of mine continued to the early twenties (i.e. trying to learn some of that Pickup Artist pseudoscience, still failing with women, while adopting misogynistic beliefs).

There may be some bizarre dating fail stories of mine, but most of them need not be mentioned, as they mostly follow the same scenarios; for example, my longest "relationship" lasted the whole five dates, ending with my "sweetheart" dumping me via text message - but this was a mere aftermath to my previous unsuccessful attempt of getting closer with her (i.e. anxiously asking for her permission to kiss her).

Mid twenties: as a fresh psychology undergrad, being exposed to some of the theories out there allowed me to tinker with myself, exploring my implicit beliefs, self-concepts, etc. Fast forward some two years, to the current day, and i know i can recognize and/or describe at least some aspects of my own damaged psyche.
Recognizing being damaged is great, in a way - had i not gotten here, i would have had a whole miserable life ahead of me, with the prospect of considering my misery as standard (many people out there live like this). However, what i still don't know is how to tackle this issue - how fix the broken aspects (keep in mind that i am no self-medicating master psychiatrist; i'm just a confused undergrad).

The prevalent issues

After reading the previous paragraphs, you may want to accuse me of being self-entitled and using that "anxious attachment" phrase as an excuse for being miserable.
And I think that being a full-blown, responsible adult that makes decisions is one thing ... while a damaged unconscious mind is something i cannot access directly and fix on the whim.

It's just that i may be standing in a random place, making a random conversation with a random person, and suddenly, in the middle of the conversation, i sneak some self-loathing words/expressions into the sentence that i'm just producing on the fly - without my conscious self neither realizing* nor wanting to devalue myself with these words.
*) not within the first second or two after saying the sentence

Having been overly criticized in my earlier years means that even today, i can't take criticism very well. Someone criticizes me, then the unpleasant feelings emerge, i start stuttering my words and then all focus is lost. And when someone actually praises me, the intense overload of positive emotion is certainly a better experience when compared to the criticism, but it still strikes as an emotional overload - off the charts of normal.

And those relationships (especially the romantic ones) - that's a whole chapter for its own. Only from books am i learning about being open to people, showing a genuine side of myself (instead of the vague, soulless protective shell of isolation), caring about my and their respective needs, etc.
Still, that anxious attachment echoes itself into my consciousness very clearly at times - there are thoughts of not being worthy of others, thoughts of others leaving me, a feeling of emptiness on the soul, and such. More often than not, these feelings are far fetched from the actual events in the real world. But these feelings are still there - and i'd like to get rid of them.

The closure (?)

Any thoughts? Ideas?

Regarding the topic, here is an interesting article (i can only say the anxious stuff mentioned in there resonates with me).

Dear Gordon.G,

I just wanted to comment on this thread because I used to be in the same shoes as you and I know how painful it can feel. The thing you have to do to overcome your problems is to change everything about your life. This is going to be scary and take a lot of time to do, but if you really want a better life, you won't let this stop you.
First, you have to embrace failure and discomfort. We all have stranger anxiety and that can make it difficult to approach women, but the thing you have to realize is at one point in your life everyone is a stranger. When you go up to a woman/ a set of women, it does not matter if you get a phone number or take them home to sleep with you. The only measurement of success you should take into consideration is if you approached her or not because that is what makes you a man. Remember, nobody closes 100% of the time. Even if the approach goes bad, you learn something and can add that experience to your belt. You will soon become comfortable approaching and with discomfort.
Second, changing. This does not mean you have to become someone completely different because that is an even bigger step in the wrong direction. What you do have to change is your mindset and realizing you already have what it takes to be successful with women. Put your past to the side because it is not there to help you, only hurt you. Hang out with people that are your heroes and who can elevate you rather than lower you or keep you the same. Envision yourself with a woman and it will happen.
Last, never stop until you get what you want. I myself am still changing and getting better. I used to be in the exact same shoes as you but when I compare myself to what I was in January, there is a night and day difference. You have to realize that this transformation could take years to months. I have come to understand that when we are old and dying, the only thing we will have are our memories, and the strongest ones are going to be with the women we have loved.

I hope I could help you out here, and good luck friend!