Waalakum salaam Brother.
The fact that you wrote this email, and you're feeling lifeless in the inside, and want to change it entirely, shows that there is this "you" that's still quiet alert and alive.
To get a better insight to your issue I called the office of Sayyid Sistani and they replied:
To give your self a physical boost and a fresh start, make a "Ghusl", wudhoo and pray two rakaat salah asking for Allah's forgiveness. Make a lot of dua to HIM and make sure you tell him your problems and how you want to be clean here after. This will really give you a physical move inshaAllah.
Also, in the Holy Quran, Allah (swt) says that HE will forgive all your sins even if they were as many as the pebbles in a desert. The only thing you should be having through out though is "hope" do not despair from his mercy iA.
The Qur'an (39:53): " say 'o my servants who have committed excess against their own souls, do not
despair of the mercy of Allah. Indeed Allah will forgive all sins"
Also, don't take it too hard on yourself once you have asked for forgiveness. Give yourself a chance, take it easy and inshaAllah you will be able to grow with the beautiful change you are wishing to see in the self.
FYI there was this sunni man, who had murdered an innocent individual in the times of IMAM Sajjad (as). He was so upset about the entire thing that he took it to the deserts and would only cry and curse himself. After a while, he heard that Imam Sajjad is visiting and he quickly thought of seeing him for some wise words (to him, IMAM was atleast from the children of the holy prophet (saww) and had that status in his eyes).
Upon seeing him IMAM said : what you're doing now, is worse than The sin itself. To despair yourself from the mercy of Allah is worse". Imam then advices him to ask for forgiveness from Allah and the victims family. He paid the blood money and they forgave him. He then lived under ease and always sought to see Imam for his concerns.
Atleast you haven't murdered anyone! It's just something between you and Allah, and he is someone who easily accepts! "سريع الرضا"
I make special dua for you.