can you help some-one that doesnt want to help themselfs?

Simple answer- NO

If someone just doesn't care, you can't make them want to change. I think the best thing you can do for them is to keep inviting them every so often and as you continue to get in better shape, hopefully they will see that and want in.

It doesn't matter how you feel about them. All that matters is how they feel. If they are unhappy with their weight, then they will do something about it. If not, then they will complain a bit and just stick with the way they did it before. You can't change other people's attitudes.
If they really want your help, they will ask for it. Try to be a good example, it's all you can do.

la4et is totally right: NO. We have a Wellness policy at our work (get checked each year & if you hit your wellness goals get a bonus at the end of the year). I've offered to help a few that I work with that complain about being overweight & wanting to change. I've told them about MFP, offered to loan them my DVD's and when I still had my gym membership, stay a bit late to wait for them to get off work & go to the gym with them (I cancelled my membership cuz I live too far & was getting home too late, I work out at home now in the AM's). They would say that sounded good, but when I said "Hey, I'm going to the gym, would you like to meet me there", or offered this website to track, the answer was,"well maybe I'll check it out later..." Later never came, and I finally came to the conclusion that when they're ready they'll do it themselves, thats what I did, and countess others on MFP.
Just keep doing what you're doing and if they really want it, they'll come to you and ask.
The best part is that you have ALL this support on MFP that they may never know about, and if that's the case, it's their loss (no pun intended! )

I've been trying to motivate my mom to lose the weight that she's put back on in the past year and a half. She's done it once before so it's clearly doable, but right now she's just not interested. I still talk about my progress and what I'm doing, but I can't force anything on her. I have a few friends as well that have asked me for advice and I've referred them here. You can't make anyone change, I know how many times I've been told that I should exercise more or eat better, but I didn't do a darn thing about it until I WANTED TO. Now I'm in it 100%. Some people just need something to flip a switch and get them motivated. I'll lead by example until then, and when they decide they want to change, I'll do everything I can to help.

The person in question has to be willing. If you continue to push, they will see you as being 'nagging' and will completely shut you out.

I've been working on my fitness for the past 16 months. I've lost 30+ pounds, I workout 6 days/week, walk the dogs 7 days/week, and eat clean. My husband, who is not overweight like I was, is 6'4" and 185 lbs. However, he smokes, eats sugar all day long, thrives on fast food, and has a malformed heart valve. If anyone needs to rethink his diet and smoking, it's him. If I push the issue, he totally shuts me out, smokes more and eats more junk.

That said, I REFUSE to buy him crappy foods at the grocery, and he now knows better to call me when I'm on my way home and ask me to drive through McDonald's for him. I will not support his choices, but I won't nag about them either.