<human>: Give me the gist of the text in a nutshell

My boyfriend and I have been together for 3 years and live together with a small dog. We have had a fairly rocky time together, but we love each other deeply. I have never had any reason not to trust him in terms of fidelity until today. 

Driving around today looking to find out which restaurants are open on labour day, I used his phone to do a google search. The browser automatically opened up to the last closed link which was a craigslist casual encounters ad. His history was listed below in plain site: he had been looking at several ads every day for weeks. 

When I asked him about it he minimized and lied all the way through, however all the evidence was in front of me: he had been going to CL for months every day, had set up an "alias" email, and has responded to at least one ad while I was out of town for work asking to meet up with a woman who was "only in town for a few hours". He admits to cruising, but denies that he met up with anyone, or that he has slept with anyone but me throughout the course of our relationship. 

Several months ago I caught him with an open "incognito" window on Google chrome, displaying two or three plenty of fish accounts. While I was upset, I let him know that as long as he never did that again I would be willing to forget it happened. For this reason I feel hesitant to forgive him, and I have no idea how to deal with the new information. We are definitely financially intertwined at the moment, which makes it hard for me to up and leave. 

Any advice would be greatly appreciated. This is my first LTR and I have never faced this issue. 

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<bot>: My long-term boyfriend who lives with me has been cruising craigslist and admits to responding to at least one ad. He has been caught cruising before. Is this cheating? What should I do!