One thing I would suggest is choosing your goals so that they aren't something that depends on others. Basically, you can achieve them yourself and it doesn't require the approval of anyone else.

For example your goal could be, "I'm going to take a short walk twice per week." That one doesn't depend on someone helping you, nor can anyone tell you it wasn't good enough.

By doing so, you can make your goals achievable and they don't get contaminated by someone else's negativity.