We both downloaded the app

So I don’t really know how to start this. I’m not fishing for sympathy or anything of that nature. I guess Im seeking thoughts and advice about this situation. Please refrain from bashing me. I am already in line to receive a heavy dosage. This post discusses the usage of Grindr in relationships.My boyfriend [23, m] and I [24, m] started dating in October 2016. After a month of dating I deleted Grindr. My bf deleted it about a week or so prior to me. We had discussions about it. I have some strong opinions about the app. I love and hate it. I think it can be quite toxic sometimes. I used it for chat (including pic trades) and the occasional hookup. My bf used it mainly for chat (without pic trades) and the occasional hookup.We both expressed that cheating would be a dealbreaker.A bit more background and context: My boyfriend has bipolar II. I struggle with depression and anxiety. We are both unmedicated and use alternative methods to cope. Im currently searching for another therapist. My bf cant afford his own right now. Our relationship has had ups and downs. A lot of it has been up and down due to mental health. I have spent a lot of emotional energy navigating the ups and downs. It has been hard, but worth it. The hardest part has been when my bf said he was unsure of our relationship on 3 different accounts. In hindsight, these instances averaged a couple days to a week or two of intense irritableness and seemingly indifferent attachment.After a year of dating, we decided to move in together for a trial period. We are currently in the midst of a six month lease. My bf’s mental health has honestly declined (suicidal ideation) since we moved given his employment and overall financial situation. He has evened out a bit. My own mental health has been going up and down a lot on a day to day basis.To get to the point: We both downloaded Grindr this past week to chat without each other knowing. My bf realized this last night and brought it up. The whole chatting on Grindr being a dealbreaker was thrown up in the air. None of our chats facilitated or participated in any intent to hookup. I sent a couple pics to someone. My bf admitted to downloading the app on several different occasions and chatting, but deleted them soon after each time. I didn’t download it since I first deleted it.When my bf saw the pics I sent, he lost it. I can understand that in some ways, I went a little farther. I sent private pics. He started saying I cheated on him. I don’t really have a defense other than I was in a low point. Our status was on the rocks. I was drained. I wanted to chat. I guess I drifted toward shallow validation. I would not have taken it further and hooked up with someone. It was never my intent.My issue with all this is that my bf downloaded the app as well-and on several different occasions. There is no way of knowing what he did and didn’t do. My bf and I have shattered a lot of trust. We decided that we’re both on board to try and salvage things. Im not sure if this is foolish or smart.We’re both allowed to feel how we’re feeling...although part of me thinks that we both had different understandings of “just chat.” We never went into depth about that topic from the beginning of our relationship. I guess part of me doesn’t want full blame of “cheating.”I feel very shitty, ashamed, and guilty for what I did. I think there is some fault on both sides. My bf decided that while it will take some time, he wants to reestablish as much trust as possible right now. I agreed; 100% honestly policy. Im feeling uncomfortable and told him that I need some space for the next day or two.Thank you for reading.