What should I do?

Hey folks,I need your help to save me from potential emotional pain. I apologize for the lengthy context but wanted to give you folks all the details so you can tell me the best course of action moving forward:Background – I am a 29 yo student in a University and met a cute guy (fellow student) on grindr about 2 months ago. My primary motive for being on the app was/is to find a ‘friends with benefits’ or even a fb arrangement so I’d have someone regular to have fun with and perhaps try new things in bed. I found a cute 25 yo guy (let’s call him Mike) and definitely hit it off with this person i.e. we have definitely met the ‘friends’ portion of the relationship. Now, Mike is already in a committed relationship (long distance but open i.e. both partners can f-around) so he is not comfortable with anything that may border ‘dating’ or a strong ‘emotional attachment’ (as he calls it) since he claims he is in love with his bf of 8 months who also happens to be 14 years older than him (doesn’t matter but figured I’ll mention it regardless). I appreciate his honesty and we discussed our rules at length i.e. no sleepovers, no date-like dinners and pure flesh-n-flesh fun with no attachment. But things don’t seem so simple now that we have been fooling around for the last 2 months. A quick look into the problem:(1) While we both have fooled around 2-3 times, I have noticed that I have been doing a lot of begging and pleading to get him to agree to fool around (2) Mike has a ‘short list’ of people he meets every now and then and also regularly fools around with new members from the glorious grindr community (3) While one part of me gets possessive and jealous, the other understands that he may not want a 1-1 monogamous sex buddy (4) We have met a Lot of times to hang out, grab food, get drinks but often there is a strong resistance to fuck around with me (5) I have directly discussed this with him and transparently mentioned that I am in no way getting attached to him and that, as we initially decided, we should just work on the benefits portion of this weird relationshipClimax – We recently got out for a weekend together and I was hopeful that I would be able to get him more comfortable with fooling with me or at least as comfortable (frequency terms) as he is with following around with all his other new weekly partners. However, prior to the trip, Mike explicitly mentioned that we will not have sex "during this trip". I was a little disappointed but figured he didn’t want to cross any boundaries in his existing relationship. However, on this trip, Mike was cruising around in the gay bars we visited and deserted me for hours to speak to this new guy he really liked and wanted to fuck. For some reason, I was really taken aback. I felt very humiliated and developed a strong complex that perhaps there is something wrong about me that is not being verbalized. To add insult to injury, he clearly articulated that we would sleep separately that night but had already made plans to meet this cute dude from the bar the next day. I was devastated.Advice Needed – I think I know what I am supposed to do but I will withhold mentioning it here so I can get some unbiased opinions about what you think I should do next. Should I keep the friend part alive even though it is not what I am looking for? Should I confront him and tell him how I felt? Will this make him have ‘pity’ sex with me? Shouldn't the intimacy rules apply to all the people he meet and, if so, do you think he is being honest about his exploits with his partner and the boundaries in their relationship? Should I just be happy with the rather forced sex that we have every 3-5 weeks? Should I take the hint that he is not really interested in what he said he was interested in and just move on? What else should I consider?Hoping your comments will save me a boatload of pain in the future. Help me reddit!