I'm in a really similar situation but M. Also 34, also had to return to my home country for 3 months, planning on a future and blindsided after cheating. I think one of the most helpful things I've heard is that 'sometimes these things just don't make sense, and you have to be ok with that and never getting an answer'. Acceptance was very to come too (still not sure I'm 100% there) and the betrayal and never being giving a chance to work on any issues after 8 years together was devastating but it does get better with time. Accept the pain for now, you're going to have to sit in it for a while. Could be a classic dismissive running from commitment, so look into that. Journal and exercise and talk it out. DMs are open if you need. All the best