Why are ‘men’ like this?

I have a complicated relationship setup with this guy,we started off as online friends sharing common interests in music,basically talking literally everyday till it eventually turned sexual online,aside from the sex,therr was chemistry between us but I thought that was silly to say since we haven’t met in person,after months of our conversations online,we eventually met (we live a plane ride apart) and it was just there,the chemistry,the sexual energy,the feeling we’ve known each other for so long or that feeling of “I wish Ive met you earlier.

We both had been single for a year but we made it certain that we are not going to be in a relationship,it was more of a friends with benefits things,so we had a really unforbetable week and parted ways and got on with our lives though he wanted to still talk everyday and ofcourse i agreed,we sex video chat most of the time and that to him equalled to sex,for 9 months we still talk,telling whta goes on wigh our lives, during that duration we had big arguments twice, take note he was honest and straightforwrd with most things,it was his personality and most importantly was his country’s culture to be straightforward and come off as blunt, he told me about this girl he met and being paired with a month before we met up in person,and I only got mad about it because he could have told me about instead of telling me just right after we spent the week together,I ddid not like the fact he choose to not tell me about things and which to him is not “lying” of you do not tell, I cried on the phone and to my supride he was crying too and I said I dont wanna talk to him ever again if he lies on the smallest of things, I decided we did not talk for a one whole month until eventually he messaged me greeting me merry christmas and how he was so sad that we stopped talking because I was overthing when in truth it was alright because the girl did not actually liked him and all that happened was the group dinner he told me about,but if she would he would have a go I guess, don’t judge me I knew what i signed up for, I told him too that this was not gonna go anywhere so what is the point on talking everyday, he said I mattered to him,he cares about m feelings,and i told him that even a fuckbuddy has the right to demand for truth,until then he was honest about everything,about what happens to him everyday at work,what his plans are, I do feel he was sincere he wanted the best for me and cared for me,the last argument we had after that was when the calls happened only when he was ‘hard’ and unlike before when he just wants to check up on me,then ofcourse that was settled, we even look forward to the time I visit him again this year

Months go on, and it was the same old good time we have video chatting and conversating online for hours and hours,but mind you,on those big arguments we had,it was like he was ashamed or felt kind of forced to admit that he could not let me go because i mattered to him that I was special to him,his line was always “why whould I not talk to you” “you tend to iverthink things that are not serious for me” and girls! Female instincts are definitely true and it was the first time i felt it with him and it was right, I message him out of random on a Monday,telling him “my hunch tells me you have been naughty this weekend””arent you gonna tell me about your weekend and how your house keys ended up on a female friend for 10 years’ bag” and he saif bluntly “oh my fuckbuddy,we decided we should not be fuckbuddys anymore”and I was like “wait what?youve been fucking someone all along” ang he said “its not like that she liked me too much,we started having sex a month ago and the other day but during those times i still call you,i check up on you like the usual,we have online sex,plus it is not a big deal I know her for 10years and she threw herself to me and she has a boyfriend who is being a jerk now so i said to myself ‘whatever fuck it’ but i never plan on having a relationship with her,she likes me too much and i dont like her that much, i still want to talk to you,our conversations make me happy” and I replied “can you hear yourself right now?you want to keep me on the side until you are done manipulating this girl who for all i know you could fuck later,tomorrow,on the day after tomorrow and still say i want to stop being fuckbuddys with her,and whats more worse you act like its not a big deal,i am over reacting again,you act like nithing fucking happens on your bedroom,her bedroom,and all the while still video caht with me and ask me how my day was” i cried so hard but I fully decided I never wanna takm to him again. I dont how a guy’s mind works but he was so sincere about saying he wants to keep me while having no sex feeling with this girl, I know from the start I was right I should have cut it off our first argument,but I mean the chemistry was just there,and he was always the one to keep insisting he wants to keep me,a part of me knows he did really found me special and that is why it hurts. Girls,you could give advice or just hear me out,i dont know if I made a concise and understandable summary of everything as i am not a native english speaker,but its quite puzzlimg how guys are as well,i thought we are only one who are complicated with our mind and feelings