Oh, mopsytop, despite the delight of having minimopsy all happy and energetic again, that all sounds like total sensory overload, you poor thing! Once you've have DC2, instead of the oft-recommended "spa day", why not go in a flotation tank instead, which is meant to be total sensory deprivation: weightlessness, total darkness and utter silence. It sounds great for most of us, but you probably need it most! Take it easy!
Oi, you seem to be constantly hyper-conscious of DH's sadness and loneliness, but it's not clear if this is from him or whether you are empathising/ projecting? If his emotions are clear, that's one thing, but if he's hiding his feelings, does he want to detatch or not? Beware of "responsibility" for his feelings, because while you promote that (either secretly, to yourself, or to him), it's not a separation, but some kind of regime of unacknowledged, asymmetric responsibilities. Is this your parents' insistence on putting up and shutting up, playing out in you, in a slightly cryptic fashion?
Also, when BOi starts spending what sounds like fairly equal time with you and DH, maybe you could try to compartmentalise a bit more? After all, if you're facilitating DH's relationship with BOi when B is with you and when B is with H, that's rather asymmetric, too! Don't give up your time with BOi to DH if DH doesn't give up his time with BOi to you!
Apologies for the lecture! 
You're welcome to lecture me back for patronising, shouting, neglecting my children and the housework and all the other vices I'm not going to admit to here! 
NorthernChinchilla, that sounded an unnecessarily harsh meeting-marathon! I hope you managed to stop thinking about it before the meeting continued in your dreams!
I hope the funeral passes without incident, figster. If there's any Twonager nonsense and you can't stay, you can always have your own memorial alone, later. In any case, remembering the dead is a practice to renew, not a one-off obligation. Today is not your only chance, so even if your poorly boy seems to ruin it (so sorry for the assumption which shows no faith in him, but we all know they are unpredictable so-and-sos, especially when ill), or cut it short for you, there will be other occasions and ways to mourn and celebrate. ((()))
After that sombreness, some good news from me this morning: I've obtained a reprieve (of one week out of two) from the hot-weather holiday with DH and the DC this summer! We were due to go away this Friday for 2.5 weeks (the nice holiday, at the lakeside), then 2 weeks at home with guests, then nearly 2 weeks away at the Overheated Seaside with DH's parents (with no time in between the different stages, with the builders threatening that they may run out of things to do if they didn't get decisions from us in a timely manner, and the house-move still hanging over our heads. Oh, and DS going back to school the day after we returned). It was an absolutely punishing schedule, especially overtiring for the DC and me, and I had been dreading the summer (which is a really perverse and crappy result of lots of "holidays" - why bother?!) Now there's an extra week at home, with my mother staying, so I can spend a window of time every day with the builders, do a bit more packing, do some LAUNDRY (after a fortnight of 6 people in the house!). And one week less at the Overheated Seaside! 
I'm really not an ungrateful bitch; I'm just grateful for different things! Although if I'm grateful for a chance to do laundry, maybe I'm not an ungrateful bitch but a crazy one!