Ex boyfriend

Hi all I split from my ex of 10 years 4 months ago, but we still get on really well and spend time together and occasionally have Sex he says he doesn't love me but whenever he hears that I spoke to other boys he doesn't like it I have told him he can't keep being like it, he has been texting flirty to another girl and has said it doesn't mean anything x I have recently been going out on the back if his bike too xI love spending time with him and am nit under the wrong impression at all.I see it as being friends.but I find it weird we get on at well :/ what impression would you be under or do you all think? x