I have been struggling with this particular mikhshol since I was about 16/17 years old.
In highschool my struggle was extremely difficult. It got to the point where I would miss school to delve into sessions of seeing inappropriate material on the internet and being motzi zerah levatala.
Thank God, I soon grew out of that intense form of addiction, but the general addiction to the material has never left me. Eeven while studying in Israel for 2 years I stumbled often. Don't get me wrong, I learned a lot. And, in general, I didn't have access to the material. However, I then turned to my imagination or to regular old pictures in an everyday newspaper. But I did have 2 months where I was clean. Only a month!!! Others tell me they could go for longer even if they stumble, but I have never beaten that record.
Afterward I went to university. For a time I struggled as intensely as before I left for Israel, however, with God's help I found my wife and for about a month things in the department of this particular sturggle were great. Before I got married I worked my way down in terms of the things I looked at and I also got an accountability program on my computer. It helped a lot thank God.
While I had never really used my smartphone to look at innaparopriate things before, I began to about a month after I got married. At first it was much milder, but now I've almost fallen to the level I was at before I got the accountability program on the computer. I have the same program on my phone but there are ways around it. I also don't want to get rid of the phone as i need it for school and work.
Long story short, I hate that I'm addicted. It makes me feel guilty and powerless. I have felt far from God for so long and I do not want to be a failure in the eyes of my wife and God. It gets in the way of my overall happiness, and threatens to ruin the happiness of others.
I want to be a good person, friend, husband and Jew.
I know I can do it, I just need someone to guide me home.

Welcome aboard!
Realize you are not alone! We are all in it together. I would start by reading the handbook and getting the chizuk emails. You will realize how many people have similar stories. Also make sure that you have cleared your mind and are truly ready to make the effort to recover! Don't look at the past just look at the NOW. Now is the time to become the warrior of Hashem. Prepare the weapons and get ready for battle! Good luck and keep posting!

one important step to take at this point is to figure out whether you're an addict or not. If you are addicted (like me), you would take different steps than someone who is not.
Regarding your smart phone, not sure which one you have, but I know from my own experience how hard it is to use them properly if you're an addict. I use an iphone and the only fool proof thing for me has been to disallow all browsers (including accountability browsers) and also all apps that could have triggering material (btw, lots of google apps allow you to search within the apps, making them browsers for all intents and purposes). I can still use the email which is enough for me. It turns out I don't miss having internet on my phone at all...

Welcome fellow struggler.
Yes, marriage doesn't cure this disease. Only recovery does.
Gazing and fantasy are the two main ways we get our lust fix.
Married men have a third way, and that is having relations with an inappropriate attitude. But let's leave that one for later.

A shortcut to recovery is to cut yourself off completely from the drug (lust).
For you (and most) this means very aggressive shmiras eynayim in all settings and media. Don't look at fully-dressed tznius women. Not even their faces. Not even ugly ones. Not even old ones. Be very, very committed to this. You can start this moment. Make it automatic to turn your head away whenever a woman appears on the radar.

For the fantasies, you will need help from Above. Whenever I detect a fantasy or lustful image trying to take hold of my mind, I block it by saying this tefilah:

"Ribbono Shel Olam, I am powerless over lust and my life has become unmanageable.
Only you can restore me to sanity.
I turn my life and my lust over to your care and ask you to please heal me from this illness of lust. I don't want to lust, I only want You and a relationship with You and Your Torah, and appropriate attraction to my wife. Take my lust. Please, take my lust."

Personalize it if you like. In the beginning I would say this dozens of times a day. Sometimes over and over. As soon as the thoughts come. Including the thought that you want to look at stuff on your phone.

Work on internalizing the message. Your goal is to give up lust itself.
Not appropriate, loving relations with your wife. Just lust.

This addiction can reconnect you to Hashem in a new and wonderful way. Because you will learn that Hashem is your only hope.

Hatzlocha!
Alex

Thank you all for all of your help and support.
All of your ideas have been really helpful.
Is there anyone I can contact before my next fall for some support? The hardest thing is right before a fall its like I become someone else. No amount of inner arguing helps. I mean sometimes it does, but sometimes its like my inside doesn't even want to struggle.

Hi friend,
I never won an argument with myself regarding watching inappropriate stuff or letting my fantasies run amock with consequent self-sex.
I learnt to give up the fight and ask for help, either from G-d (by praying) or from a fellow struggler (by calling). So you're right about this part.
If you PM me, I'll be happy to exchange phone numbers so you can call regularly BEFORE getting into a loosing argument with youself.
Mottel

Thank you.
What does PM mean?
Shabbat Shalom

"Private message". It's an icon under my name. Since you're new to the forum, I'd like to get to know you a bit better to feel safe giving you my phone number. If you "private message" me your real first name and phone number, I'll reply in kind and be happy to take your calls.
BTW, this free service is available to anyone who is interested. I am in touch via telephone with a bunch of us nutcases here on GYE, and as far as I can tell everyone benefits from this.
Shabat Shalom,
Mottel