Should I leave or try to talk it out?

Good afternoon Lau, and thank you so much for asking your question. 

First off, let me begin by saying I am sorry that your partner was sending photos to other girls during your relationship. I can only begin to imagine how you felt when you found out, and how that may continue to affect the relationship. In regards to what you feel like you should do (stay in the relationship or leave), I would encourage you to do a couple of things before making that decision. One recommendation would be to have another discussion with your partner, especially if he is continuing to send photos, or flirtatious content to other women. Setting a boundary with him is going to be very important, and when he pushes back, or disrespects this boundary, then it is up to you on how you want to respond to that boundary being violated. I would also encourage you to journal, or write out your feelings towards him sending photos to other women, and review what you write to help in processing your feelings, and ultimately come to a decision. 

Another strategy that can be helpful is to write down a pros and cons list, or an outcomes list of what it would look like if you were to make either decision. (To leave the relationship or continue). This may help you identify what the best decision would be for you, as well as recognizing the feelings of the outcome you would want to follow through with. You mentioned that you feel like you cannot trust him anymore, so my question back to you is, "Do you think that trust can be repaired?". Do you want to be in a relationship without trust, and if so, what does that relationship look and feel like for you? 

Making a decision like the one you are faced with is not easy, so I certainly encourage you to take some time and process your feelings on what you would like to do. I hope the above strategies can be helpful for you moving forward. Best of luck to you, and thank you so much for your question!