1 "I need to do this for my health"
"If a male doesn't ejaculate for a long period of time nothing noticeable happens. There is no buildup of pressure or extra sperm. Our bodies are always reabsorbing and disposing of extra material, including excess components of the ejaculate. It is perfectly natural to not ejaculate for a long period of time. There are no risks or heath problems associated with not ejaculating."
A quote from Guard Your Eyes Handbook
2 "I need to do this in order to quiet my yetzer ra (evil inclination)"
We all know that a rash is very hard to leave alone and that scratching it does not make it better. In the same way this does not quiet the inclination but on the contrary, awakens it.
"There is a small organ in a man, if one feeds it - it is hungry, if one starves it - it is satisfied. " Chazal
3 "I can do this to a certain point and then stop when it is necessary to"
Recalculate...bad habits grow strong very quickly… when they reach a certain point, they are not that easy to stop.
"In the beginning , the passions are as travelers carrying out a brief stay among us ; then they are guests who visit us daily and ultimately they become absolute masters of our will ."
Avot de Raba Natan 89
4 "This is my pleasure"
This is not a real pleasure but a counterfeit pleasure.
Your gain is the immediate cheap thrill (which is used to habituate you, so it is not really your pleasure). A real assessment of the situation will show you that your losses are heavy indeed and nothing can justify them.
5 "I am too weak to quit"
This is not a myth!
Studying Torah daily for a certain amount of time daily is a sure and effective way to acquire the strength to beat this terrible, destructive habit.
Even so did the Holy One, blessed be He, speak unto Israel: ‘My children! I created the Evil Desire, but I [also] created the Torah, as its antidote; if you occupy yourselves with the Torah, you will not be delivered into his hand." Talmud Kidushin 30b