sweetie here is a huge hug....much love and huggies

Lots of big warm huggs honey, as weird as this may sound. Walk away, you already see whats going on, as much as you want answers and explanations it might be a bit easier on your heart if you just leave him alone. He should not be giving you reasons to not feel secure in his love for you. Frankly you're too young to be experiencing such heart ache. Speaking from experience, it might just be easier to count your losses and move on. HTH

Time to walk away and have sme time to collect your thoughts.
If it doesnt feel right then its most likely correct ,
Hugs and love to you. theres always someone to relpace him
Cheers Pete

From past experience - if it seems like there is something no quite right- trust your intuition. The penance to pay for not doing so is very high in the long term. I would set an ultimatum - either he talks about what the problem is or you leave it (as you are not happy with the way things are) and if he is fine with that - then he chose for you to leave - it was his choice. If he doesnt want you to leave, he will talk about the problem and you resolve it together to make for a decent relationship worth being in (remember, relationship should be fun, not ardous) or he admits he wants to be with someone else and it ends that way.
sorry if this sounds very very blunt - it is just i have been through such things before and have always been glad in the long rn of being totally objective in my behaviour. it is hard when you are in teh sitaution and clouded with emoitons etc- but you must must admit- you would prob give the same advice to a friend objectively - yes.
good luck
x

"I would set an ultimatum - either he talks about what the problem is or you leave it (as you are not happy with the way things are)"

There's no need to give someone an ultimatum.  That is one's own need to try and control another's behavior.  If you are not happy with the way things are, then choose to leave for yourself.  The results will be the same for him..either he'll talk and work to improve things or not.  The bigger reward and difference is that you acted and behaved from your own personal power space and knowing what is best for you, like a strong, confident & capable person.