Partner distant after TC

2 minute read time.

So back in early 2015 my partner was diagnosed TC (early stage in the left side). He was diagnosed early Feb and operated on end of Feb 2015. Since his TC things have not been the same between us. Here's the chain of events that occurred:

1) he broke up with me Jan 2015, not telling me why. Just said 'he wants to break up and doesn't know what will happen'.

2) I tried to contact him here and then the next few weeks and only got minimal response or something nothing at all

3) by April/ may 2015 he started  forward again - and at this point I still don't know about the TC

4) June 2015 my friend see him online a dating app, this obviously caused an argument between us and I accused him of cheating (thinking this is why he broke up with me in the first place). He deleted his profile and then told me he was diagnosed with something. He didn't want to talk about it and but a few weeks later he opened up and told me he was diagnosed with TC. This was when I first found out. 

I literally broke down. I was so upset and being in a long distance relationship didn't help either. I just wanted to see him but every time we'd agree to meet he would cancel/ignore me last minute. When we finally met in October 2015 ( yes a very long wait) it was great. 

But once we had met he had become distant again. I felt he was making excuses to not meet up... He then went back on the dating app and when I found out it was really upsetting. I asked him about it again and he deleted his profile and promised he hasn't met any one from there. We moved on from this and continued to talk. But he had become upset with himself for how he's been towards me over then months. He became depressed saying; he's struggling; he hates how he's treated me and I deserve better etc. I've tried to talk to him but nothing seems to work and I don't know what to do anymore. I know he's been through a tough time but this whole experience has been unpleasant for me and made me feel insecure and knocked my confidence. Especially because of the dating app incident. I just feel like why did he need to go on there?! I just want to understand what he must of been going through mentally and impact on his confidence etc? Does TC give individuals low sex drive? He said he suffers from pain every now and then around the scar tissue, is this common? 

Many thanks 
RS 
Anonymous