Little bit of background to start with - I broke up with my ex DP 2 years ago after realising I no longer loved him. Split was fairly painless and everything works very well as co-parents to our 5 year old DS. We see each other most days as I do the morning routine and he does the evenings (at my house) until I return from work. Neither of us have family close by and so we need to rely on each other a fair bit and remain as flexible as we can.
Ex DP has had several girlfriends over the 2 years, but nothing has worked out. I was single for the whole time up until 7 months ago when I met my DP. Nothing has changed between myself and ex DP, things have virtually carried on as before, although there are less times were we may do something all together, as a family. I'd like to stress that there have never been any blurred lines with our relationship since we broke up. Everything is purely for the sake of our DS and his benefit / welfare. As an example - we might all go to the park together once in a blue moon if we're both around etc.
The summer holidays have been reasonably challenging and holidays and plans have all been relatively last minute due to money constraints for both of us (2 houses in SW London are expensive to run)!
Myself, my DP and DS have just been on holiday for 2 weeks to Greece and had a great time, further cementing our relationship. Ex DP has just arranged to take DS to Dorset next week for a few days to camp and fossil hunt, something which I suggested and offered him the use of my car for ages days. He's always been insured on it as he doesn't have his own and if he ever needs to use it to take DS anywhere. My DP is clearly not happy about me offering to let him use the car and is pretty grumpy about me helping him to organise the trip. He also mentioned a few weeks ago that he was occasionally jealous of our close relationship, despite the fact I have repeatedly made it clear it is purely for my DS's benefit. AIBU to think that he needs to accept the situation as it is, or do I need to change my approach to the relationship with my ex DP?