Support forums like this exist because unless you're in this situation, i.e. needing to lose weight and all the emotional baggage that inevitably goes with that, another person may not truly understand what it is like to go through it, and what a big deal even the smallest losses and gains really are to the person that is going through it. Some partners/family/friends pay lip service just because they realise that it's important to you, even if they don't really understand it, and often that's as good as it gets. Some people are luckier than that and have people who are genuinely pleased and supportive of your quest. However, there are those who just really don't get it, and really just don't understand how defeating they are by not taking the interest that you need, or being supportive of you whether you're up or down, as it's a rollercoast ride when you're on a weight loss journey. Some people might make innocent little jokes or jibes that they mean with good humour as it's the only thing they can think to do, without truly realising the hurt or frustration they may be causing.
I think the most important thing is that YOU are aware of what you're going though and why. It really doesn't matter what anyone else thinks as this journey is for you and your own health and wellbeing. You can get a lot more support than people that are going it alone, just by being on this forum where you can talk freely about your feelings and get feedback from people that are going through the same thing as you... and that puts you in a stronger position than some!
You've taken a brave decision to face a big weight loss journey as it will change your life in so many ways, and that's as scary as it is exciting. Well done you on being so brave! Keep going, don't let anyone get in your way of doing this!