Any advice on how to get over this / not let it affect me?

[CalonHapus]

A few of my wife's relatives have become markedly less friendly to me since our daughter was born (not that they were ever mad keen on me before...because of the whole 'lesbian thing').

We were with everyone for Easter yesterday and one of these relatives starting talking to my wife about an upcoming event for DD and not including me in the conversation even though I was standing right there (and was trying to join in).

She later brought around presents for everyone apart from me and my DS (everyone else had got presents for all of us but she only got them for DW and DD).

When we first saw her after DD was born, she warmly congratulated DW and then turned to me and said 'oh I suppose it's congratulations for you too, isn't it' in a flat tone.

Another relative will now only grudgingly say hello to me and makes a big show of how DW is DD's 'mamma', ignoring DW whenever she says 'yes, I'm DD's mummy and CalonHapus is her mami'.

I don't know if they're just passive-aggressively 'telling' me that they don't consider me to be DD's parent?!

It has really hurt and upset me and has left a dark cloud over an otherwise really lovely celebration. I don't want to feel so affected. Objectively I know that their opinions have no bearing on anything - I will continue being DD's mami regardless of what they think about that - but I don't want them living rent-free in my head like this.

Has anyone been in a similar situation and managed to find a (healthy) way to deal with it?

I am sorry that this happened to you.
People can be hugely thoughtless.

@CalonHapus I'm sorry they made you feel crap. People are really thoughtless sometimes. 💐❤️

Hello.
My MiL is like this with DS, her only grandchild, I suspect because she isn't biologically related to him. She has said some really thoughtless/hurtful things in the past. She just can't understand that DW does the majority of childcare as I work as I earn more, she thinks I should stay at home like he is my sole responsibility. She does get pulled up on it by SiL and DW but if that happens she usually digs her heels in so its pointless.

We solved this by reducing our visits from 4/5× a year to once. DW usually goes in between. Thankfully she lives 100 miles away!

What does your wife say/do in these situations?

Wow I'm really sorry you are going through this. How does your wife feel about her family being so cruel- the present thing is bonkers!
Whist you say that their 'opinions will have no baring' may be true whilst DD is little, continuing to have these people in your DD life whilst treating you like this will become apparent to your DD as she grows up and could create a sense of insecurity, feeling that she has to 'choose', feeling sad at seeing her mum treated poorly by people she is supposed to love. You mention a DS too- I'm presuming you are bio parent. Is your wife his second mum or step mum? Not that it makes much difference because if.your wife has any active role in his life then this inevitably be damaging for him too feeling ostracised or different to his sister.
I'm sorry- no shade- but I really think your wife needs to step up and do more here. As bio mum to DD, if my wife (and other child) were treated like this then I would be having strong words about how unacceptable it is and potentially cutting them off if their behaviour doesn't change