We are NOT angels, unfortunately. This is a major strength point in Islam and that is one of the causes of its being a practical up-to-date religion. Islam does not treat a Muslim as an angel to be, no Islam understands human nature and its flaws and very slowly sets you on a trip for betterment. To prove my point I can give some examples such as:
1- Gradual Prohibition
Many essential rulings in Islam were legislated gradually like banning alcoholic drinks. At that time in the Arabian peninsula Arabs loved drink alcoholic drinks and yes, some were addicted to it., besides a whole economy was raised around their trade. Islam did not just ban alcoholic drinks all of a sudden regardless of what Muslims would suffer Psychologically and financially. Banning of Alcoholic drinks was on three steps:
First, He made it clear to them that the harm of drinking alcohol is greater than its benefit. This is clear in the verse: "They ask you about wine and gambling. Say, "In them is great sin and [yet, some] benefit for people. But their sin is greater than their benefit." (2:219)
Second: He told the Muslims not to come to prayer while intoxicated. This is clear in the verse: "O you who have believed, do not approach prayer while you are intoxicated until you know what you are saying or in a state of janabah, except those passing through [a place of prayer], until you have washed [your whole body]." (4:43)
Third: Total Prohibition. This is clear in the verse: "O you who have believed, indeed, intoxicants, gambling, [sacrificing on] stone alters [to other than Allah], and divining arrows are but defilement from the work of Satan, so avoid it that you may be successful." (5:90)
2- Repentance...an Always-Open door
Repentance is always available to anyone who commits any sin and without any go-between.
There are various verses telling people not to fear or hesitate to repent.
For example: "Ask your Lord for forgiveness and then turn in repentance to Him," (11:3)
"Indeed, Allah loves those who are constantly repentant and loves those who purify themselves." (2:222)
There are however conditions for repentance to be accepted:
3- To Sin...is Not the end of the world
In the Holy Quran God says: "Say, "O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful." (39:53)
Prophet Muhammad, peace and blessings be upon him, says: "By He in whose hand is my soul, if you did not sin, GOD would wipe you out and bring into existence people who did sin, ask God for forgiveness - and He would forgive them."(Muslim). Also he, peace and blessings be upon him, says: "All the sons of Adam are sinners and the best among the sinners are those who repent." (Ahmad and others)
At-Tirmidhi and others reported on the authority of Anas ibn Maalik who said, ‘I heard the Messenger of GOD, peace and blessings be upon him, saying: “GOD says, ‘O son of Adam! As long as you call unto me and seek (forgiveness from) me, I will forgive you for all of the sins that you may commit and I do not care (how many they amount to). O son of Adam! If you come to me with what is almost as much as the earth (in volume) in sins, but you meet me without having associated any partner with Me in worship, I will give you the same amount of forgiveness.’
The Messenger of GOD, peace and blessings be upon him, therefore used to seek GOD’s forgiveness frequently during the day and night and said of himself, ‘I swear by GOD, I seek GOD’s forgiveness and repent to Him seventy times a day.’ (Bukhaari).
4- Enjoying life is NOT a sin
A- Hanzalah Al-Usayyidi, May Allah be pleased with him, who was one of the scribes of Messenger of Allah, peace and blessings be upon him, reported:
I met Abu Bakr, May Allah be pleased with him, he said: "How are you O Hanzalah?"
I said, "Hanzalah has become a hypocrite".
He said, "Far removed is Allah from every imperfection, what are you saying?"
I said, "When we are in the company of Messenger of Allah, peace and blessings be upon him, and he reminds us of Hell-fire and Jannah, we feel as if we are seeing them with our very eyes, and when we are away from Messenger of Allah, peace and blessings be upon him, we attend to our wives, our children, our business, most of these things (pertaining to life hereafter) slip out of our minds."
Abu Bakr, May Allah be pleased with him, said, "By Allah, I also experience the same thing".
So Abu Bakr, May Allah be pleased with him, and I went to Messenger of Allah, peace and blessings be upon him, and I said to him, "O Messenger of Allah, peace and blessings be upon him, Hanzalah has turned hypocrite."
Thereupon Messenger of Allah, peace and blessings be upon him, said, "What has happened to you?"
I said, "O Messenger of Allah, when we are in your company, and are reminded of Hell-fire and Jannah, we feel as if we are seeing them with our own eyes, but when we go away from you and attend to our wives, children and business, much of these things go out of our minds."
Thereupon Messenger of Allah , peace and blessings be upon him, said, "By Him in Whose Hand is my life if your state of mind remains the same as it is in my presence and you are always busy in remembrance (of Allah), the angels will shake hands with you in your beds and in your roads; but Hanzalah, time should be devoted (to the worldly affairs) and time should be devoted (to prayer)". He (the Prophet , peace and blessings be upon him) said this thrice. (narrated by Muslim, Riyad as-Salihin)
B- In Sunan an-Nasa'i 3217 that It was narrated by Anas that there was a group of the Companions of the Prophet, one of whom said: "I will not marry women." Another said: "I will not eat meat." Another said: "I will not sleep on a bed." Another said: "I will fast and not break my fast." News of that reached the Messenger of Allah and he praised Allah then said: "What is the matter with people who say such and such? But I pray and I sleep, I fast and I break my fast, and I marry women. Whoever turns away from my Sunnah is not of me."
C- Abu Hurairah, may Allah be pleased with him, reports, The companions asked, "O Messenger of Allah, you joke with us?" Prophet Muhammad, peace and blessings be upon him, replied, "Yes, I do not say but the truth." ( Shama'il Muhammadiyah (virtues of the Prophet)- Description Of The Joking Of Prophet Muhammad, peace and blessings be upon him, book 35 Hadith 227)
Abu Dharr narrated that the Messenger of Allah said : "Your smiling in the face of your brother is charity, commanding good and forbidding evil is charity, your giving directions to a man lost in the land is charity for you. Your seeing for a man with bad sight is a charity for you, your removal of a rock, a thorn or a bone from the road is charity for you. Your pouring what remains from your bucket into the bucket of your brother is charity for you." (Jami` at-Tirmidhi 1956)
Islam does not want to make life difficult or expect from us what we are not. Islam wants you to enjoy life without offending others. Enjoy that you are rich but remember the poor. Joke and laugh but not on the expense of others. A Muslim is jovial not gloomy, convinces people not scream at them. I know that seeing the attitude of some Muslims today is quite different from what I am telling you, but remember that is THEIR attitude which couldn't be farthest from what Islam actually calls for.